Vacation at Miami Beach, Florida, USA

Miami Beach is a huge city with several district articles containing sightseeing, restaurant, nightlife and accommodation listings — consider printing them all.
Miami Beach is a city in Florida. This small barrier island near Miami was originally cleared of  mangroves in the late 1800's to make way for a coconut farm, and was later incorporated as a city by real estate developers in 1915.

Climate

Despite occasional cold snaps, Miami Beach is known for its genrally warm, muggy weather. Located just above the Tropic of Cancer, Miami Beach has a subtropical climate, with dry, warm winters and springs, and hot, humid and rainy summers and falls. Miami Beach, due to ocean breezes, has lower humidity and heat than inland areas in South Florida, and also does not get as cool as inland South Florida during cold spells.

Districts

Although tourists generally consider Miami Beach to be part of Miami, it is in actuality its own municipality. Located on a barrier island east of Miami and Biscayne Bay, it is home to a large number of beach resorts and is one of the most popular spring break party destinations in the world. Because of its length, it is generally broken up into three districts.
Mid Beach
Often known just as "Miami Beach", this district refers to the "Mid-beach" area between 23rd Street and 63rd Street.

South Beach Southern tip of the island to about 23rd Street.

North Beach Northern tip of the island, from about 63rd Street on up

Understand

Miami Beach is a barrier island connected to the mainland city of Miami by a series of bridges.
Miami Beach, like Miami, has a huge Latin American population, and Spanish is a language often used for day-to-day discourse in many places. However, English is the language of preference, particularly when dealing with businesses and government. Spanglish, a mixture of English and Spanish, is a somewhat common occurrence, with bilingual locals switching between English and Spanish mid-sentence. The local Latin population is mostly Cuban exiles (which have now become second and third generation locals,) with South Americans from various countries gaining ground. There is also a large Haitian community and many signs and public announcements are in English, Spanish and Creole.
Miami Beach has been one of America's pre-eminent beach resorts for almost a century. The city of Miami Beach is a barrier island connected to the mainland city of Miami by a series of bridges. The city is often referred to under the umbrella term of "Miami”, with a population of 87,925. As a world-class destination, Miami Beach offers several kinds of lodging options. The visitor can stay in a normal hotel or choose from a variety of Miami Beach vacation rentals. Visitors can plan to stay in a Miami Beach condo rental. Miami Beach has a rich history as a trend setting arts center from the world famous nightclubs of the 1950s, to the rich cultural life of today's modern South Beach. The City of Miami Beach has an identity that is intrinsically linked to the arts, and today the entertainment, production and arts communities are stronger than ever. Miami Beach is truly a major international entertainment and cultural destination.
If you come to Miami to shop, then Miami Beach can give you the best shopping experience ever. With the famous Lincoln Road Mall and glamorous shopping centers located in South Beach and all over the island, you’ll have great options to spend your time and money in the trendy retails stores that carry garments from international designers. Art museums, ballet performances, cultural events and entertainment are a part of this great city. You will have the chance to choose from a wide variety of Miami attractions. Art Center at Lincoln Road has performance art exhibitions. Classes and courses are available as well and they include photography, jewelry-making and painting.
Beyond the radiant sun, surf and sand, discover Miami Beach’s rich history as an entertainment and cultural destination, from world-famous Art Deco architecture to renowned nightclubs to designer fashions on Collins Ave and Lincoln Rd. There’s so much going on in Miami Beach, you will need an extra day to enjoy everything that makes this city so vibrant. Plan to lodge in an affordable Miami vacation home and completely enjoy the world’s elite playground. Miami Beach promises a 25-hour day, and whether you're an arts enthusiast, a socialite or a sun worshipper, there are plenty of options for where to spend that extra hour.

By plane

Miami International Airport (MIA) is closest, but Fort Lauderdale International Airport (FLL) is only around 40 minutes away (depending on traffic) by shuttle and the rates are often better.
You can take the J or 150 Bus from Miami International Airport to Miami Beach. To Get to South Beach, then transfer to a southbound C, L, or S bus. The fare is approximately $2. If you get the 150, you can also transfer to the South Beach Local at the last stop.
From Fort Lauderdale Airport, you can take the #1 Broward County bus to Aventura Mall for the Miami-Dade S bus.

Get around

Taxis are generally expensive, but available at almost any time and place. Car rentals are the most convenient form of transportation for visitors, with local companies offering better prices but national chains offering more convenience regarding return policies and shop times.

Public Transportation

When traveling within Miami Beach, a good choice is the South Beach Local, a shuttle bus that operates in a loop from 19th St to the southern end of Miami Beach (buses travel in both clockwise and counterclockwise directions). Fare is only 25 cents. Regional transit buses throughout the greater Miami area are available, but may be slow and inconvenient. Schedules and routes are available from the Miami-Dade Transit website or by calling +1 305 770 3131.

By electric golf cart

South Beach Decocarts, 1000 5th St, +1 786 383 2278  is the newest addition with stylish Eco-friendly golf cart rentals. Hourly, daily and weekly rentals are available. Each Decocart can fit 4 adults (great for groups) and requires a driver's license. It can hold shopping bags and other items you won't be able to transport with a bike or scooter. Decocarts also offers trendy E-Bikes that don't require a license.


By bike
Miami Beach has become more bicycle friendly in recent years with the addition of new bike paths and bike lanes, although not as comprehensive as other major cities. Notable additions to the biking and pedestrian infrastructure include the paved "Beach Walk" which runs parallel to Ocean Drive and Collins Avenue and is directly on the beach, plus the new South Point Park along the bay. In Miami Beach and South Beach riding is permitted on sidewalks, which luckily are wider than average. That said, it doesn't stop many people from trying to utilize bicycles (including locals) to get around town. Pedestrians and drivers tend to be tolerant of bikers and willing to share the right of way. However, be prepared to slow down and go on foot, particularly on the congested streets closer to the beach. Absent heavy auto traffic, South Beach is biking bliss.
There are better attempts at bike-friendliness in the South Beach district, where most of the bike rental shops are located. Lummus Park and Lincoln Road Mall are great for bikers, and have plenty of bike racks throughout; meanwhile, if you are trying to go north or south, go a few blocks west and take one of the roads less traveled. Meridian Ave is a good choice: plenty of interesting Miami-style houses to see and a local park. If you didn't bring your own bike, bike rentals will run about $8/hour or $30/day (or 24-hour time period).

• City of Miami Beach "DecoBike" Official Bike Rental & Sharing Program, 723 Washington Ave., +1 305 532 9494. Rent a bike from any of 100 stations in the city and simply drop off to any station when done. DecoBike provides maps for self-guided Art Deco bike tours. Available to both residents and visitors.

• Miami Beach Bicycle Center, 601 5th St, +1 305 674 0150.

• Two Wheel Drive, 1260 Washington Ave, +1 305 534 2177.

• Bike and Roll, 760 Washington, +1 305 538 2121 

 By free taxi

They say there's no such thing as a free ride, but that's exactly what SWOOP Miami (+1 305 409-6636) is. Supported by advertisements, the SWOOP taxi is a six-passenger white electric golf cart that will pick you up and take you anywhere within South Beach — no fee or fare required, although the drivers will gladly accept tips. Call ahead to be picked up within 15 minutes, anytime between noon and 2AM daily. Unfortunately, though they have "Miami" in the name, they won't go outside the South Beach district.




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Rail transport

Rail transport is a means of conveyance of passengers and goods by way of wheeled vehicles running on rail tracks. It is also commonly referred to as Train transport. In contrast to road transport, where vehicles merely run on a prepared surface, rail vehicles are also directionally guided by the tracks on which they run. Track usually consists of steel rails installed on sleepers/ties and ballast, on which the rolling stock, usually fitted with metal wheels, moves. However, other variations are also possible, such as slab track where the rails are fastened to a concrete foundation resting on a prepared subsurface.

Rolling stock in railway transport systems generally has lower frictional resistance when compared with highway vehicles, and the passenger and freight cars (carriages and wagons) can be coupled into longer trains. The operation is carried out by a railway company, providing transport between train stations or freight customer facilities. Power is provided by locomotives which either draw electrical power from a railway electrification system or produce their own power, usually by diesel engines. Most tracks are accompanied by a signalling system. Railways are a safe land transport system when compared to other forms of transport.[Nb 1] Railway transport is capable of high levels of passenger and cargo utilization and energy efficiency, but is often less flexible and more capital-intensive than highway transport is, when lower traffic levels are considered.

The oldest, man-hauled railways date to the 6th century B.C, with Periander, one of the Seven Sages of Greece, credited with its invention. Rail transport blossomed after the British development of the steam engine as a viable source of power in the 18th and 19th centuries. With steam engines, it was possible to construct mainline railways, which were a key component of the industrial revolution. Also, railways reduced the costs of shipping, and allowed for fewer lost goods. The change from canals to railways allowed for "national markets" in which prices varied very little from city to city. Studies have shown that the invention and development of the railway in Europe was one of the most important technological inventions of the late 19th century for the United States, without which, GDP would have been lower by 7.0% in 1890. In the 1880s, electrified trains were introduced, and also the first tramways and rapid transit systems came into being. Starting during the 1940s, the non-electrified railways in most countries had their steam locomotives replaced by diesel-electric locomotives, with the process being almost complete by 2000. During the 1960s, electrified high-speed railway systems were introduced in Japan and a few other countries. Other forms of guided ground transport outside the traditional railway definitions, such as monorail or maglev, have been tried but have seen limited use.
History

The history of the growth, decline and resurgence of rail transport can be divided up into several discrete periods defined by the principal means of motive power used.
Pre-steam
Horsecar in Brno, Czech Republic

The earliest evidence of a railway was a 6-kilometre (3.7 mi) Diolkos wagonway, which transported boats across the Corinth isthmus in Greece during the 6th century BC. Trucks pushed by slaves ran in grooves in limestone, which provided the track element. The Diolkos ran for over 600 years.[1]

Railways began reappearing in Europe after the Dark Ages. The earliest known record of a railway in Europe from this period is a stained-glass window in the Minster of Freiburg im Breisgau in Germany, dating from around 1350.[2] In 1515, Cardinal Matthäus Lang wrote a description of the Reisszug, a funicular railway at the Hohensalzburg Castle in Austria. The line originally used wooden rails and a hemp haulage rope, and was operated by human or animal power. The line still exists, albeit in updated form, and is one of the oldest railways still to operate.[3][4]

By 1550, narrow gauge railways with wooden rails were common in mines in Europe.[5] By the 17th century, wooden wagonways were common in the United Kingdom for transporting coal from mines to canal wharfs for transshipment to boats. The world's oldest working railway, built in 1758, is the Middleton Railway in Leeds. In 1764, the first gravity railroad in the United States was built in Lewiston, New York.[6] The first permanent tramway was the Leiper Railroad in 1810.[7]

The first iron plate railway made with cast iron plates on top of wooden rails, was taken into use in 1768.[8] This allowed a variation of gauge to be used. At first only balloon loops could be used for turning, but later, movable points were taken into use that allowed for switching.[9] From the 1790s, iron edge rails began to appear in the United Kingdom.[10] In 1803, William Jessop opened the Surrey Iron Railway in south London, arguably the world's first horse-drawn public railway.[11] The invention of the wrought iron rail by John Birkinshaw in 1820 allowed the short, brittle, and often uneven, cast iron rails to be extended to 15 feet (4.6 m) lengths.[12] These were succeeded by steel in 1857.[10]
Age of steam
A British steam locomotive-hauled train
Tren a las Nubes (Train to the Clouds), located in Salta, Argentina

The development of the steam engine during the Industrial revolution in the United Kingdom spurred ideas for mobile steam locomotives that could haul trains on tracks. James Watt's patented steam engines of 1769 (revised in 1782) were heavy low-pressure engines which were not suitable for use in locomotives. However, in 1804, using high-pressure steam, Richard Trevithick demonstrated the first locomotive-hauled train in Merthyr Tydfil, United Kingdom.[13][14] Accompanied with Andrew Vivian, it ran with mixed success,[15] breaking some of the brittle cast-iron plates.[16] Two years later, the first passenger horse-drawn railway was opened nearby between Swansea and Mumbles.[17]
Earliest British steam railways

In 1811, John Blenkinsop designed the first successful and practical railway locomotive[18]—a rack railway worked by a steam locomotive between Middleton Colliery and Leeds on the Middleton Railway. The locomotive, Salamanca, was built the following year.[19]:20 In 1825, George Stephenson built the Locomotion for the Stockton and Darlington Railway, north east England, which was the first public steam railway in the world. In 1829, he built The Rocket which was entered in and won the Rainhill Trials. This success led to Stephenson establishing his company as the pre-eminent builder of steam locomotives used on railways in the United Kingdom, the United States and much of Europe.[19]:24–30

In 1830, the first intercity railway, the Liverpool and Manchester Railway, opened. The gauge was that used for the early wagonways and had been adopted for the Stockton and Darlington Railway.[20] The 1,435 mm (4 ft 8 1⁄2 in) width became known as the international standard gauge, used by about 60% of the world's railways. This spurred the spread of rail transport outside the UK.

By the early 1850s Britain had over 7,000 miles of railway, 'a stunning achievement given that only twenty years had elapsed since the opening of the Liverpool and Manchester Railway.[21]
Early railroads in the US

Railroads (as they are known in the US) were built on a far larger scale than those in Continental Europe, both in terms of the distances covered and also in the loading gauge adopted, which allowed for heavier locomotives and double-deck trains.

The railroad era in the United States began in 1830 when Peter Cooper's locomotive, Tom Thumb, first steamed along 13 miles (21 km) of Baltimore and Ohio railroad track.[22] In 1833, the nation's second railroad ran 136 miles (219 km) from Charleston to Hamburg in South Carolina.[23] Not until the 1850s, though, railroads offered long distance service at reasonable rates. A journey from Philadelphia to Charleston involved eight different gauges, which meant that passengers and freight had to change trains seven times. Only at places like Bowling Green, Kentucky, the railroads were connected to one another.

The Baltimore and Ohio that opened in 1830 was the first to evolve from a single line to a network in the United States.[24] By 1831, a steam railway connected Albany and Schenectady, New York, a distance of 16 miles, which was covered in 40 minutes.[25]

The years between 1850 and 1890 saw phenomenal growth in the US railroad system, which at its peak constituted one third of the world's total mileage.[26][not in citation given] Although the American Civil War placed a temporary halt to major new developments, the conflict did demonstrate the enormous strategic importance of railways at times of war. After the war, major developments include the first elevated railway built in New York in 1867 as well as the symbolically important first transcontinental railroad was completed in 1869.[27]
Electrification and dieselisation
0-Series Shinkansen, introduced in 1964, triggered the intercity train travel boom.
Elevated section of the Chicago 'L'
Luas in Dublin, Ireland

Experiments with electrical railways were started by Robert Davidson in 1838. He completed a battery-powered carriage capable of 6.4 km/h (4 mph). The Gross-Lichterfelde Tramway was the first to use electricity fed to the trains en route, when it opened in 1881. Overhead wires were taken into use in the Mödling and Hinterbrühl Tram in Austria in October 1883. At first, this was taken into use on tramways that, until then, had been horse-drawn tramcars. The first conventional completely electrified railway mainline was the 106 km Valtellina line in Italy that was opened on 4 September 1902. During the 1890s, many large cities, such as London, Paris and New York City used the new technology to build rapid transit for urban commuting. In smaller cities, tramways became common and were often the only mode of public transport until the introduction of buses in the 1920s. In North America, interurbans became a common mode to reach suburban areas. At first, all electric railways used direct current but, in 1904, the Stubaital Line in Austria opened with alternating current.[28]

Steam locomotives require large pools of labour to clean, load, maintain and run. After World War II, dramatically increased labour costs in developed countries made steam an increasingly costly form of motive power. At the same time, the war had forced improvements in internal combustion engine technology that made diesel locomotives cheaper and more powerful. This caused many railway companies to initiate programmes to convert all unelectrified sections from steam to diesel locomotion.

Following the large-scale construction of motorways after the war, rail transport became less popular for commuting and air transport started taking large market shares from long-haul passenger trains. Most tramways were either replaced by rapid transits or buses, while high transshipment costs caused short-haul freight trains to become uncompetitive. The 1973 oil crisis led to a change of mind set and most tram systems that had survived into the 1970s remain today. At the same time, containerization allowed freight trains to become more competitive and participate in intermodal freight transport. With the 1964 introduction of the Shinkansen high-speed rail in Japan, trains could again have a dominant position on intercity travel. During the 1970s, the introduction of automated rapid transit systems allowed cheaper operation. The 1990s saw an increased focus on accessibility and low-floor trains. Many tramways have been upgraded to light rail and many cities that closed their old tramways have reopened new light railway systems.
Innovations

Many benchmarks in equipment and infrastructure led to the growing use of railways. Some innovative features taking place in the 19th and 20th centuries included wood cars replaced with all-steel cars, which provided better safety and maintenance; iron rails replaced with steel rails, which provided higher speed and capacity with lower weight and cost; stove-heated cars to steam-heating cars, piped from locomotive; gas lighting to electric lighting, with use of battery/alternator unit beneath the car; development of air-conditioning with additional underbody equipment and ice compartment. Some innovative rolling stock included the lightweight, diesel-powered streamliner, which was a modernistic, aerodynamically styled train with flowing contours; then came the ultra-lightweight car with internal combustion engine in each train's power car; others included the dome car, turbined-powered trains, bilevel rolling stock, and the high-tech/high-speed electric trains.[29]

Even more, in the first half of the 20th century, infrastructure elements adopted technological changes including the continuously welded rail that was 1/4 miles long; concrete tie usage; double tracking major lines; intermodal terminal and handling technology; advances in diesel-electric propulsion to include AC traction systems and propulsion braking systems; and just-in-time inventory control. Beyond technology, even management of systems seen improvements with the adoption of environmental impact concerns; heightened concern of employee and public safety; introduction of urban area rail networks and public agencies to manage them; and downsizing of the industry employment with greater use of contractors and consultants.[30]
Trains
Main article: Train

A train is a connected series of rail vehicles that move along the track. Propulsion for the train is provided by a separate locomotive or from individual motors in self-propelled multiple units. Most trains carry a revenue load, although non-revenue cars exist for the railway's own use, such as for maintenance-of-way purposes. The engine driver controls the locomotive or other power cars, although people movers and some rapid transits are driverless.
Haulage
Russian 2TE10U diesel locomotive

Traditionally, trains are pulled using a locomotive. This involved a single or multiple powered vehicles being located at the front of the train and providing sufficient adhesion to haul the weight of the full train. This remains dominant for freight trains and is often used for passenger trains. A push-pull train has the end passenger car equipped with a driver's cab so the engine driver can remotely control the locomotive. This allows one of the locomotive-hauled train's drawbacks to be removed, since the locomotive need not be moved to the end of the train each time the train changes direction. A railroad car is a vehicle used for the haulage of either passengers or freight.

A multiple unit has powered wheels throughout the whole train. These are used for rapid transit and tram systems, as well as many both short- and long-haul passenger trains. A railcar is a single, self-powered car. Multiple units have a driver's cab at each end of the unit and were developed following the ability to build electric motors and engines small enough to fit under the coach. There are only a few freight multiple units, most of which are high-speed post trains.
Motive power
A RegioSwinger multiple unit of the Croatian Railways

Steam locomotives are locomotives with a steam engine that provides adhesion. Coal, petroleum, or wood is burned in a firebox. The heat boils water in the fire-tube boiler to create pressurized steam. The steam travels through the smokebox before leaving via the chimney. In the process, it powers a piston that transmits power directly through a connecting rod (US: main rod) and a crankpin (US: wristpin) on the driving wheel (US main driver) or to a crank on a driving axle. Steam locomotives have been phased out in most parts of the world for economical and safety reasons although many are preserved in working order by heritage railways.

Electric locomotives draw power from a stationary source via an overhead wire or third rail. Some also or instead use a battery. A transformer in the locomotive converts the high voltage, low current power to low voltage, high current used in the electric motors that power the wheels. Modern locomotives use three-phase AC induction motors. Electric locomotives are the most powerful traction. They are also the cheapest to run and provide less noise and no local air pollution. However, they require high capital investments both for the overhead lines and the supporting infrastructure. Accordingly, electric traction is used on urban systems, lines with high traffic and for high-speed rail.

Diesel locomotives use a diesel engine as the prime mover. The energy transmission may be either diesel-electric, diesel-mechanical or diesel-hydraulic but diesel-electric is dominant. Electro-diesel locomotives are built to run as diesel-electric on unelectrified sections and as electric locomotives on electrified sections.

Alternative methods of motive power include magnetic levitation, horse-drawn, cable, gravity, pneumatics and gas turbine.
Passenger trains
Interior view of the top deck of a VR InterCity2 double-deck carriage

A passenger train travels between stations where passengers may embark and disembark. The oversight of the train is the duty of a guard/train manager. Passenger trains are part of public transport and often make up the stem of the service, with buses feeding to stations. Passenger trains can involve a variety of functions including long distance intercity travel, daily commuter trips, or local urban transit services. They even include a diversity of vehicles, operating speeds, right of way requirements, and service frequency. Passenger trains usually can be divided into two operations: intercity railway and intracity transit. Whereas as intercity railway involve higher speeds, longer routes, and lower frequency (usually scheduled), intracity transit involves lower speeds, shorter routes, and higher frequency (especially during peak hours).[30]

Intercity trains are long-haul trains that operate with few stops between cities. Trains typically have amenities such as a dining car. Some lines also provide over-night services with sleeping cars. Some long-haul trains been given a specific name. Regional trains are medium distance trains that connect cities with outlying, surrounding areas, or provide a regional service, making more stops and having lower speeds. Commuter trains serve suburbs of urban areas, providing a daily commuting service. Airport rail links provide quick access from city centres to airports.

High-speed rail are special inter-city trains that operate at much higher speeds than conventional railways, the limit being regarded at 200 to 320 km/h. High-speed trains are used mostly for long-haul service and most systems are in Western Europe and East Asia. The speed record is 574.8 km/h (357.2 mph), set by a modified French TGV.[31][32] Magnetic levitation trains such as the Shanghai airport train use under-riding magnets which attract themselves upward towards the underside of a guideway and this line has achieved somewhat higher peak speeds in day-to-day operation than conventional high-speed railways, although only over short distances. Due to their heightened speeds, route alignments for high-speed rail tend to be steeper grades and broader curves compared to conventional railways. Their high kinetic energy translates to higher horsepower-to-ton ratios (20 hp/ton); this allows trains to accelerate and maintain higher speeds and negotiate steep grades as momentum builds up and recovered in downgrades (reducing cut, fill, and tunneling requirements). Since lateral forces act on curves, curvatures are designed with the highest possible radius. All these features are dramatically different from freight operations, thus justifying exclusive high-speed rail lines if it is economically feasible.[30]
Rail Network in Paris, France

Rapid transit is an intracity system built in large cities and has the highest capacity of any passenger transport system. It is grade separated and commonly built underground or elevated. At street level, smaller trams can be used. Light rails are upgraded trams that have step-free access, their own right-of-way and sometimes sections underground. Monorail systems operate as elevated, medium capacity systems. A people mover is a driverless, grade-separated train that serves only a few stations, as a shuttle. Due to the wide variety of rapid transit systems without much uniformity, route alignment vary widely with diverse right-of-ways (private land, side of road, street median) and geometric characteristics (sharp or broad curves, steep or gentle grades). For instance, the Chicago El trains are designed with extremely short cars to negotiate the sharp curves in the Loop. NJ's PATH have similar-sized cars to accommodate curves in the trans-Hudson tunnels. San Francisco's BART operate large cars on its well-engineered routes.[30]
Freight train
Main article: Rail freight transport
Bulk cargo of minerals

A freight train hauls cargo using freight cars specialized for the type of goods. Freight trains are very efficient, with economy of scale and high energy efficiency. However, their use can be reduced by lack of flexibility, if there is need of transshipment at both ends of the trip due to lack of tracks to the points of pick-up and delivery. Authorities often encourage the use of cargo rail transport due to its environmental profile.[33]

Container trains have become the dominant type in the US for non-bulk haulage. Containers can easily be transshipped to other modes, such as ships and trucks, using cranes. This has succeeded the boxcar (wagon-load), where the cargo had to be loaded and unloaded into the train manually. The intermodal containerization of cargo has revolutionized the supply chain logistics industry, reducing ship costs significantly. In Europe, the sliding wall wagon has largely superseded the ordinary covered wagons. Other types of cars include refrigerator cars, stock cars for livestock and autoracks for road vehicles. When rail is combined with road transport, a roadrailer will allow trailers to be driven onto the train, allowing for easy transition between road and rail.

Bulk handling represents a key advantage for rail transport. Low or even zero transshipment costs combined with energy efficiency and low inventory costs allow trains to handle bulk much cheaper than by road. Typical bulk cargo includes coal, ore, grains and liquids. Bulk is transported in open-topped cars, hopper cars and tank cars.

Dance

Dance is a type of art that generally involves movement of the body, often rhythmic and to music. It is performed in many cultures as a form of emotional expression, social interaction, or exercise, in a spiritual or performance setting, and is sometimes used to express ideas or tell a story. Dance may also be regarded as a form of nonverbal communication between humans or other animals, as in bee dances and behaviour patterns such as a mating dances.

Definitions of what constitutes dance can depend on social and cultural norms and aesthetic, artistic and moral sensibilities. Definitions may range from functional movement (such as folk dance) to virtuoso techniques such as ballet. Martial arts kata are often compared to dances, and sports such as gymnastics, figure skating and synchronized swimming are generally thought to incorporate dance. In some cases, the motion of ordinarily inanimate objects may be described as dance (the leaves danced in the wind).

There are many styles and genres of dance. African dance is interpretative. Ballet, ballroom and tango are classical dance styles. Square dance and electric slide are forms of step dance, and breakdancing is a type of street dance. Dance can be participatory, social, or performed for an audience. It can also be ceremonial, competitive or erotic. Dance movements may be without significance in themselves, as in ballet or European folk dance, or have a gestural vocabulary or symbolic meaning as in some Asian dances.

Choreography is the art of creating dances. The person who creates (i.e., choreographs) a dance is known as the choreographer.
 Origins and history
Main article: History of dance
Ancient Greek bronze statuette of a veiled and masked dancer, 3rd - 2nd century BC, found in Alexandria, Egypt.

Dance does not leave behind clearly identifiable physical artifacts such as stone tools, hunting implements or cave paintings. It is not possible to say when dance became part of human culture.

Joseph Jordania recently suggested that dance, together with rhythmic music and body painting, was designed by the forces of natural selection at the early stage of hominid evolution as a potent tool to put groups of human ancestors in a battle trance, a specific altered state of consciousness. In this state hominids were losing their individual identity and were acquiring collective identity.[1] Jonathan Pieslak's research shows that some contemporary military units use loud group singing and dancing in order to prepare themselves for the dangerous combat missions.[2] According to Jordania, this trance-inducing ability of dance comes from human evolutionary past and includes as well a phenomenon of military drill[3] which is also based on shared rhythmic and monotonous group activity.

Dance has certainly been an important part of ceremony, rituals, celebrations and entertainment since before the birth of the earliest human civilizations. Archeology delivers traces of dance from prehistoric times such as the 9,000 year old Rock Shelters of Bhimbetka paintings in India and Egyptian tomb paintings depicting dancing figures from c. 3300 BC.

One of the earliest structured uses of dances may have been in the performance and in the telling of myths. It was also sometimes used to show feelings for one of the opposite gender. It is also linked to the origin of "love making." Before the production of written languages, dance was one of the methods of passing these stories down from generation to generation.[4]

Another early use of dance may have been as a precursor to ecstatic trance states in healing rituals. Dance is still used for this purpose by many cultures from the Brazilian rainforest to the Kalahari Desert.[5]

Sri Lankan dances goes back to the mythological times of aboriginal yingyang twins and "yakkas" (devils). According to a Sinhalese legend, Kandyan dances originated 250 years ago, from a magic ritual that broke the spell on a bewitched king. Many contemporary dance forms can be traced back to historical, traditional, ceremonial, and ethnic dance.
Classification and genres

Partner Dancing in Art
Dance at Bougival by Pierre-Auguste Renoir (1882–83)
Eadweard Muybridge's phenakistoscope "A Couple Waltzing" (c.1893)
Main articles: List of basic dance topics and List of dances

Dance categories by number of interacting dancers are mainly solo dance, partner dance and group dance. Dance is performed for various purposes like ceremonial dance, erotic dance, performance dance, social dance etc.
Dancing and music
Morris dancing in the grounds of Wells Cathedral, Wells, England
See also: Category:Music genres

Many early forms of music and dance were created and performed together. This paired development has continued through the ages with dance/music forms such as: jig, waltz, tango, disco, salsa, electronica and hip-hop. Some musical genres have a parallel dance form such as baroque music and baroque dance; others, such as classical music and classical ballet, developed separately.

Although dance is often accompanied by music, it can also be presented independently or provide its own accompaniment (tap dance). Dance presented with music may or may not be performed in time to the music depending on the style of dance. Dance performed without music is said to be danced to its own rhythm[citation needed].

Ballroom dancing is a dance art form which combines athletic fitness with artistically skillful dance steps.
Dance studies and techniques
See also: Dance theory, Choreography, and Dance moves

In the early 1920s, dance studies (dance practice, critical theory, Musical analysis and history) began to be considered as an academic discipline. Today these studies are an integral part of many universities' arts and humanities programs. By the late 20th century the recognition of practical knowledge as equal to academic knowledge led to the emergence of practice research and practice as research. A large range of dance courses are available including:

    Professional practice: performance and technical skills
    Practice research: choreography and performance
    Ethnochoreology, encompassing the dance-related aspects of: anthropology, cultural studies, gender studies, area studies, postcolonial theory, ethnography, etc.
    Dance therapy, or dance-movement therapy
    Dance and technology: new media and performance technologies
    Laban Movement Analysis and somatic studies

Academic degrees are available from BA (Hons) to PhD and other postdoctoral fellowships, with some dance scholars taking up their studies as mature students after a professional dance career.
Dance competitions
An amateur dancesport competition at MIT

A dance competition is an organized event in which contestants perform dances before a judge or judges for awards, and in some cases, monetary prizes. There are several major types of dance competitions, distinguished primarily by the style or styles of dances performed. Major types of dance competitions include:

    Competitive dance, in which a variety of theater dance styles such as: acro, ballet, jazz, hip-hop, lyrical, and tap, are permitted.
    Open competitions, that permit a wide variety of dance styles. A popular example of this is the TV program So You Think You Can Dance.
    Dancesport, which is focused exclusively on ballroom and latin dance. Popular examples of this are TV programs Dancing with the Stars and Strictly Come Dancing.
    Single-style competitions, such as; highland dance, dance team, and Irish dance, that only permit a single dance style.

Today, there are various dances and dance show competitions on television and the Internet.
Occupations
Main article: List of dance occupations
Saman dance from Gayo people of Sumatra, Indonesia

There are several careers connected with dancing: Dancer, dance teacher, dance sport coach, dance therapist and choreographer.

Dancer

Dance training differs depending on the dance form. There are university programs and schools associated with professional dance companies for specialised training in classical dance (e.g. Ballet) and modern dance. There are also smaller, privately owned dance studios where students may train in a variety of dance forms including competitive dance forms (e.g. Latin dance, ballroom dance, etc.) as well as ethnic/traditional dance forms.

Professional dancers are usually employed on contract or for particular performances/productions. The professional life of a dancer is generally one of constantly changing work situations, strong competition pressure and low pay. Professional dancers often need to supplement their income, either in dance related roles (e.g., dance teaching, dance sport coaches, yoga) or Pilates instruction to achieve financial stability.

In the U.S. many professional dancers are members of unions such as the American Guild of Musical Artists, the Screen Actors Guild and Actors' Equity Association. The unions help determine working conditions and minimum salaries for their members.
Professional dancers at the Tropicana Club, Havana, Cuba, in 2008

Dance teachers

Dance teacher and operators of dance schools rely on reputation and marketing. For dance forms without an association structure such as Salsa or Tango Argentino they may not have formal training. Most dance teachers are self-employed.

Dancesport coaches

Dancesport coaches are tournament dancers or former dancesports people, and may be recognised by a dance sport federation.

Choreographer

Choreographers are generally university trained and are typically employed for particular projects or, more rarely may work on contract as the resident choreographer for a specific dance company. A choreographic work is protected intellectual property. Dancers may undertake their own choreography.
By ethnicity or region
Main article: List of ethnic, regional, and folk dances sorted by origin
India
South indian folk dance like a horse known as Poi Kal Kudirai
Main article: Dance in India

During the first millennium BCE in India, many texts were composed which attempted to codify aspects of daily life. In the matter of dance, Bharata Muni's Natyashastra (literally "the text of dramaturgy") is one of the earlier texts. Though the main theme of Natyashastra deals with drama, dance is also widely featured, and indeed the two concepts have ever since been linked in Indian culture. The text elaborates various hand-gestures or mudras and classifies movements of the various limbs of the body, gait, and so on. The Natyashastra categorised dance into four groups and into four regional varieties, naming the groups: secular, ritual, abstract, and, interpretive. However, concepts of regional geography has altered and so have regional varieties of Indian dances. Dances like "Odra Magadhi", which after decades long debate, has been traced to present day Mithila, Odisha region's dance form of Odissi (Orissi), indicate influence of dances in cultural interactions between different regions.[6]

From these beginnings rose the various classical styles which are recognised today. Therefore, all Indian classical dances are to varying degrees rooted in the Natyashastra and therefore share common features: for example, the mudras, some body positions, and the inclusion of dramatic or expressive acting or abhinaya. The Indian classical music tradition provides the accompaniment for the dance, and as percussion is such an integral part of the tradition, the dancers of nearly all the styles wear bells around their ankles to counterpoint and complement the percussion.
Bhangra in the Punjab
Main article: Bhangra

The Punjab area overlapping India and Pakistan is the place of origin of Bhangra. It is widely known both as a style of music and a dance. It is mostly related to ancient harvest celebrations, love, patriotism or social issues. Its music is coordinated by a musical instrument called the 'Dhol'. Bhangra is not just music but a dance, a celebration of the harvest where people beat the dhol (drum), sing Boliyaan (lyrics) and dance.It developed further with the Vaisakhi festival of the Sikhs.
Dances of Sri Lanka
Main article: Dances of Sri Lanka

The devil dances of Sri Lanka or "yakun natima" are a carefully crafted ritual with a history reaching far back into Sri Lanka's pre-Buddhist past. It combines ancient "Ayurvedic" concepts of disease causation with psychological manipulation. The dance combines many aspects including Sinhalese cosmology, the dances also has an impact on the classical dances of Sri Lanka.[7]
Harlequin and Columbine from the mime theater at Tivoli Gardens, Copenhagen, Denmark
In Europe and North America
Concert (or performance) dance
Main article: Concert dance
Ballet
Main article: Ballet

Ballet developed first in Italy and then in France from lavish court spectacles that combined music, drama, poetry, song, costumes and dance. Members of the court nobility took part as performers. During the reign of Louis XIV, himself a dancer, dance became more codified. Professional dancers began to take the place of court amateurs, and ballet masters were licensed by the French government. The first ballet dance academy was the Académie Royale de Danse (Royal Dance Academy), opened in Paris in 1661. Shortly thereafter, the first institutionalized ballet troupe, associated with the Academy, was formed; this troupe began as an all-male ensemble but by 1681 opened to include women as well.[4]
A small dance company rehearses for an outdoor performance in Stuyvesant Cove Park in Manhattan, New York City
20th-century concert dance
Main article: 20th century concert dance

At the beginning of the 20th century, there was an explosion of innovation in dance style characterized by an exploration of freer technique. Early pioneers of what became known as modern dance include Loie Fuller, Isadora Duncan, Mary Wigman and Ruth St. Denis. The relationship of music to dance serves as the basis for Eurhythmics, devised by Emile Jaques-Dalcroze, which was influential to the development of Modern dance and modern ballet through artists such as Marie Rambert. Eurythmy, developed by Rudolf Steiner and Marie Steiner-von Sivers, combines formal elements reminiscent of traditional dance with the new freer style, and introduced a complex new vocabulary to dance. In the 1920s, important founders of the new style such as Martha Graham and Doris Humphrey began their work. Since this time, a wide variety of dance styles have been developed; see Modern dance.
The influence of African American dance
Main article: African American dance

African American dances are those dances which have developed within African American communities in everyday spaces, rather than in dance studios, schools or companies and its derivatives, tap dance, disco, jazz dance, swing dance, hip hop dance and breakdance. Other dances, such as the lindy hop with its relationship to rock and roll music and rock and roll dance have also had a global influence.

U.S. state

A state of the United States of America is one of the fifty constituent political entities that shares its sovereignty with the United States federal government. Because of the shared sovereignty between each U.S. state and the U.S. federal government, an American is a citizen of both the federal republic and of his or her state of domicile.[1] State citizenship and residency are flexible and no government approval is required to move between states, except for persons covered by certain types of court orders (e.g., paroled convicts and children of divorced spouses who are sharing custody).

States are divided into counties or county-equivalents, which may be assigned some local governmental authority but are not sovereign. County or county-equivalent structure varies widely by state. Kentucky, Massachusetts, Pennsylvania, and Virginia use the official title of Commonwealth rather than State.

The United States Constitution allocates certain powers to the federal government. It also places limitations on the federal and state governments. State governments are allocated power by the people (of each respective state) through their individual constitutions. By ratifying the United States Constitution, the states transferred certain limited sovereign powers to the federal government. Under the Tenth Amendment, all powers not delegated to the federal government nor prohibited to the states are retained by the states or the people.

Historically, the tasks of public safety (in the sense of controlling crime), public education, public health, transportation, and infrastructure have generally been considered primarily state responsibilities, although all of these now have significant federal funding and regulation as well (based largely upon the Commerce Clause, the Taxing and Spending Clause, and the Necessary and Proper Clause of the U.S. Constitution).

Over time, the U.S. Constitution has been amended, and the interpretation and application of its provisions have changed. The general tendency has been toward centralization and incorporation, with the federal government playing a much larger role than it once did. There is a continuing debate over states' rights, which concerns the extent and nature of the states' powers and sovereignty in relation to the federal government as well as the rights of individual persons. Debates over states' rights were a contributing factor to the outbreak of the American Civil War.

The United States Congress may admit new states on an equal footing with existing ones; this last happened in 1959 with the admission of Alaska and Hawaii. The U.S. Constitution is silent on the question of whether states have the power to leave unilaterally, or secede from, the Union, but the U.S. Supreme Court has ruled[2][3] secession to be unconstitutional, a position driven in part by the outcome of the American Civil War.

Main article: List of U.S. states

 Alabama
 Alaska
 Arizona
 Arkansas
 California
 Colorado
 Connecticut
 Delaware
 Florida
Georgia      Hawaii
 Idaho
 Illinois
 Indiana
 Iowa
 Kansas
 Kentucky
 Louisiana
 Maine
 Maryland      Massachusetts
 Michigan
 Minnesota
 Mississippi
 Missouri
 Montana
 Nebraska
 Nevada
 New Hampshire
 New Jersey      New Mexico
 New York
 North Carolina
 North Dakota
 Ohio
 Oklahoma
 Oregon
 Pennsylvania
 Rhode Island
 South Carolina      South Dakota
 Tennessee
 Texas
 Utah
 Vermont
 Virginia
 Washington
 West Virginia
 Wisconsin
 Wyoming

Federal power

The Supreme Court of the United States has interpreted the Commerce Clause of the Constitution of the United States which has expanded the scope of federal power. The Cambridge Economic History of the United States says, "On the whole, especially after the mid-1880s, the Court construed the Commerce Clause in favor of increased federal power."[4] In Wickard v. Filburn 317 U.S. 111 (1942), the court expanded federal power to regulate the economy by holding that federal authority under the commerce clause extends to activities which are local in character.[5] For example, Congress can regulate railway traffic across state lines, but it may also regulate rail traffic solely within a state, based on the theory that wholly intrastate traffic can still have an impact on interstate commerce. In recent years, the Court has tried to place limits on the Commerce Clause in such cases as United States v. Lopez and United States v. Morrison.[clarification needed]

Another source of congressional power is its spending power—the ability of Congress to impose taxes and distribute the resulting revenue back to the states (subject to conditions set by Congress). A classic example of this is the system of federal-aid highways, which includes the Interstate Highway System. The system is mandated and largely funded by the federal government, and also serves the interests of the states. By threatening to withhold federal highway funds, Congress has been able to pressure state legislatures to pass a variety of laws. Although some object that this infringes on states' rights, the Supreme Court upheld the practice as a permissible use of the Constitution's Spending Clause in South Dakota v. Dole 483 U.S. 203 (1987).
Governments

States are free to organize their individual governments any way they like, so long as they conform to the sole requirement of the U.S. Constitution that they have "a Republican Form of Government," that is, each state government must be a republic.
Constitutions

In practice, each state has adopted a three-branch system of government (with legislative, executive, and judiciary branches) generally along the same lines as that of the federal government — though this is not a requirement.

Despite the fact that every state has chosen to follow the federal model of government, there are significant differences in some states.

There are also significant similarities. For example, all 50 states allow tax exemptions for religious institutions.[6]
Executive

In all of the U.S. states, the chief executive is called the Governor. The governor may approve or veto bills passed by the state legislature. In forty-three states, governors have line item veto power.[7]

Most states have a "plural executive" in which two or more members of the executive branch are elected directly by the people. Such additional elected officials serve as members of the executive branch, but are not beholden to the governor and the governor cannot dismiss them. For example, the attorney general is elected, rather than appointed, in 43 of the 50 U.S. states.
Legislative
See also: State legislature (United States)

The legislatures of 49 of the 50 states are made up of two chambers: a lower house (termed the House of Representatives, State Assembly or House of Delegates) and a smaller upper house, always termed the Senate. The exception is the unicameral Nebraska Legislature, which is composed of only a single chamber.

Most states have part-time legislatures, while six of the most populated states have full-time legislatures. However, several states with high population have short legislative sessions, including Texas and Florida.[8]

In Baker v. Carr (1962) and Reynolds v. Sims (1964), the U.S. Supreme Court held that all states are required to elect their legislatures in such a way as to afford each citizen the same degree of representation (the one person, one vote standard). In practice, most states choose to elect legislators from single-member districts, each of which has approximately the same population. Some states, such as Maryland and Vermont, divide the state into single- and multi-member districts, in which case multi-member districts must have proportionately larger populations, e.g., a district electing two representatives must have approximately twice the population of a district electing just one.

If the governor vetoes legislation, all legislatures may override it, usually, but not always, requiring a two-thirds majority.
Judicial
See also: State court (United States) and state supreme court

States can also organize their judicial systems differently from the federal judiciary, as long as they protect the federal constitutional right of their citizens to procedural due process. Most have a trial level court, generally called a District Court or Superior Court, a first-level appellate court, generally called a Court of Appeal (or Appeals), and a Supreme Court. However, Oklahoma and Texas have separate highest courts for criminal appeals. New York state has its own terminology, in that the trial court is called the Supreme Court. Appeals are then taken to the Supreme Court, Appellate Division, and from there to the Court of Appeals.

Most states base their legal system on English common law (with substantial indigenous changes and incorporation of certain civil law innovations), with the notable exception of Louisiana, a former French colony, which draws large parts of its legal system from French civil law.

Only a few states choose to have the judges on the state's courts serve for life terms. In most of the states the judges, including the justices of the highest court in the state, are either elected or appointed for terms of a limited number of years, such as five years, eligible for re-election or reappointment if their performance is judged to be satisfactory.
Relationships
Among states

Under Article Four of the United States Constitution, which outlines the relationship between the states, the United States Congress has the power to admit new states to the Union. The states are required to give full faith and credit to the acts of each other's legislatures and courts, which is generally held to include the recognition of legal contracts, marriages, and criminal judgments, and before 1865, slavery status. States are prohibited from discriminating against citizens of other states with respect to their basic rights, under the Privileges and Immunities Clause. Under the Extradition Clause, a state must extradite people located there who have fled charges of "treason, felony, or other crimes" in another state if the other state so demands.
With the federal government

The states are guaranteed military and civil defense by the federal government, which is also required to ensure that the government of each state remains a republic.

Four states use the official name of Commonwealth, rather than State.[9] However, this is merely a paper distinction, and the U.S. Constitution uniformly refers to all of these subnational jurisdictions as "States" (Article One, Section 2, Clause 1 of the Constitution, concerning the U.S. House of Representatives, in which Representatives are to be elected by the people of the "States"; Article One, Section 3, Clause 1, concerning the U.S. Senate, allocates to each "State" two Senators). For all of these purposes, each of the four above-mentioned "Commonwealths" counts as a State.

Twitter

Twitter is an online social networking service and microblogging service that enables its users to send and read text-based messages of up to 140 characters, known as "tweets".

Twitter was created in March 2006 by Jack Dorsey and by July, the social networking site was launched. The service rapidly gained worldwide popularity, with over 500 million registered users as of 2012, generating over 340 million tweets daily and handling over 1.6 billion search queries per day.[8][10][11] Since its launch, Twitter has become one of the ten most visited websites on the Internet, and has been described as "the SMS of the Internet."[7][12] Unregistered users can read tweets, while registered users can post tweets through the website interface, SMS, or a range of apps for mobile devices.[13]

Twitter Inc. is based in San Francisco, with additional servers and offices in New York City, Boston, and San Antonio.
 History
Creation and initial reaction
A blueprint sketch, c. 2006, by Jack Dorsey, envisioning an SMS-based social network.

Twitter's origins lie in a "daylong brainstorming session" held by board members of the podcasting company Odeo. Dorsey, then an undergraduate student at New York University, introduced the idea of an individual using an SMS service to communicate with a small group.[14][15] The original project code name for the service was twttr, an idea that Williams later ascribed to Noah Glass,[16] inspired by Flickr and the five-character length of American SMS short codes. The developers initially considered "10958" as a short code, but later changed it to "40404" for "ease of use and memorability."[17] Work on the project started on March 21, 2006, when Dorsey published the first Twitter message at 9:50 PM Pacific Standard Time (PST): "just setting up my twttr".[1]

    "...we came across the word 'twitter', and it was just perfect. The definition was 'a short burst of inconsequential information,' and 'chirps from birds'. And that's exactly what the product was." – Jack Dorsey[18]

The first Twitter prototype was used as an internal service for Odeo employees and the full version was introduced publicly on July 15, 2006.[9] In October 2006, Biz Stone, Evan Williams, Dorsey, and other members of Odeo formed Obvious Corporation and acquired Odeo and all of its assets – including Odeo.com and Twitter.com – from the investors and shareholders.[19] Williams fired Glass who was silent about his part in Twitter's startup until 2011.[20] Twitter spun off into its own company in April 2007.[21]

The tipping point for Twitter's popularity was the 2007 South by Southwest Interactive (SXSWi) conference. During the event, Twitter usage increased from 20,000 tweets per day to 60,000.[22] "The Twitter people cleverly placed two 60-inch plasma screens in the conference hallways, exclusively streaming Twitter messages," remarked Newsweek's Steven Levy. "Hundreds of conference-goers kept tabs on each other via constant twitters. Panelists and speakers mentioned the service, and the bloggers in attendance touted it."[23]

Reaction at the conference was highly positive. Blogger Scott Beale said that Twitter "absolutely rul[ed]" SXSWi. Social software researcher danah boyd said Twitter "own[ed]" the conference.[24] Twitter staff received the festival's Web Award prize with the remark "we'd like to thank you in 140 characters or less. And we just did!"[25]

The first unassisted off-Earth Twitter message was posted from the International Space Station by NASA astronaut T. J. Creamer on January 22, 2010.[26] By late November 2010, an average of a dozen updates per day were posted on the astronauts' communal account, @NASA_Astronauts. NASA has also hosted over 25 "tweetups", events that provide guests with VIP access to NASA facilities and speakers with the goal of leveraging participants' social networks to further the outreach goals of NASA.

In August 2010, the company appointed Adam Bain from News Corp.'s Fox Audience Network as president of revenue.[27]

On September 14, 2010, Twitter launched a redesigned site[28] including a new logo.[citation needed]
Growth

The company experienced rapid growth. It had 400,000 tweets posted per quarter in 2007. This grew to 100 million tweets posted per quarter in 2008. In February 2010, Twitter users were sending 50 million tweets per day.[29] By March 2010, the company recorded over 70,000 registered applications.[30] As of June 2010, about 65 million tweets were posted each day, equaling about 750 tweets sent each second, according to Twitter.[31] As of March 2011, that was about 140 million tweets posted daily.[32] As noted on Compete.com, Twitter moved up to the third-highest-ranking social networking site in January 2009 from its previous rank of twenty-second.[33]
Jack Dorsey, a co-founder and the chairman of Twitter, in 2009

Twitter's usage spikes during prominent events. For example, a record was set during the 2010 FIFA World Cup when fans wrote 2,940 tweets per second in the thirty-second period after Japan scored against Cameroon on June 14, 2010. The record was broken again when 3,085 tweets per second were posted after the Los Angeles Lakers' victory in the 2010 NBA Finals on June 17, 2010,[34] and then again at the close of Japan's victory over Denmark in the World Cup when users published 3,283 tweets per second.[35] The record was set again during the 2011 FIFA Women's World Cup Final between Japan and the United States, when 7,196 tweets per second were published.[36] When American singer Michael Jackson died on June 25, 2009, Twitter servers crashed after users were updating their status to include the words "Michael Jackson" at a rate of 100,000 tweets per hour.[37] The current record as of January 1, 2013, was set by all citizens of the Japan Standard Time Zone as the new year began, reaching a record of 33,388 tweets per second (and hence beating the previous record of 25,088, also set by Japan after a television screening of the movie "Castle In The Sky").[38]

Twitter acquired application developer Atebits on April 11, 2010. Atebits had developed the Apple Design Award-winning Twitter client Tweetie for the Mac and iPhone. The application, now called "Twitter" and distributed free of charge, is the official Twitter client for the iPhone, iPad and Mac.[39]

From September through October 2010, the company began rolling out "New Twitter", an entirely revamped edition of twitter.com. Changes included the ability to see pictures and videos without leaving Twitter itself by clicking on individual tweets which contain links to images and clips from a variety of supported websites including YouTube and Flickr, and a complete overhaul of the interface, which shifted links such as '@mentions' and 'Retweets' above the Twitter stream, while 'Messages' and 'Log Out' became accessible via a black bar at the very top of twitter.com. As of November 1, 2010, the company confirmed that the "New Twitter experience" had been rolled out to all users.

On April 5, 2011, Twitter tested a new homepage and phased out the "Old Twitter."[40] However, a glitch came about after the page was launched, so the previous "retro" homepage was still in use until the issues were resolved; the new homepage was reintroduced on April 20.[41][42]

On December 8, 2011, Twitter overhauled its website once more to feature the "Fly" design, which the service says is easier for new users to follow and promotes advertising. In addition to the Home tab, the Connect and Discover tabs were introduced along with a redesigned profile and timeline of Tweets. The site's layout has been compared to that of Facebook.[43][44]

On February 21, 2012, it was announced that Twitter and Yandex agreed to a partnership. Yandex, a Russian search engine, finds value within the partnership due to Twitter’s real time news feeds. Twitter’s director of business development explained that it is important to have Twitter content where Twitter users go.[45]

On March 21, 2012, Twitter celebrated its sixth birthday while also announcing that it has 140 million users and sees 340 million tweets per day. The number of users is up 40% from their September 2011 number, which was said to have been at 100 million at the time.[46]

In April 2012, Twitter announced that it was opening an office in Detroit, with the aim of working with automotive brands and advertising agencies.[47] Twitter also expanded its office in Dublin.[48]

On June 4, 2012, Twitter announced the purchase of Washington, D.C. based web design agency Nclud. Upon the purchase, Nclud's co-founder and director of brand experience, Martin Ringlein, was named Twitter's new design manager.[49] On June 5, a modified logo was unveiled through the company blog, removing the text to showcase the slightly redesigned bird as the sole symbol of Twitter.[50]

On October 5, 2012, Twitter acquired a video clip company called Vine that launched in January 2013.[51][52] Twitter released Vine as a standalone app that allows users to create and share six-second looping video clips on January 24, 2013. Vine videos shared on Twitter are visible directly in users' Twitter feeds.[53] Due to an influx of inappropriate content, it is now rated 17+ in Apple's app store.[54]

On December 18, 2012, Twitter announced it had surpassed 200 million monthly active users. Twitter hit 100 million monthly active users in September 2011.[55]
Leadership

As chief executive officer, Dorsey saw the startup through two rounds of capital funding by the venture capitalists who backed the company.[56]

On October 16, 2008,[57] Williams took over the role of CEO, and Dorsey became chairman of the board.[58]

On October 4, 2010, Williams announced that he was stepping down as CEO. Dick Costolo, formerly Twitter's chief operating officer, became CEO. According to a Twitter blog, dated October 4, 2010, Williams was to stay[dated info] with the company and "be completely focused on product strategy."[dated info][59]

According to The New York Times, "Mr. Dorsey and Mr. Costolo forged a close relationship" when Williams was away.[60] According to PC Magazine, Williams was "no longer involved in the day-to-day goings on at the company". He is focused on developing a new startup, but he became a member of Twitter's board of directors, and promised to "help in any way I can". Stone is still with Twitter but is working with AOL as an "advisor on volunteer efforts and philanthropy".[61]

Dorsey rejoined Twitter in March 2011, as executive chairman focusing on product development. His time is split with Square (where he is CEO), whose offices are within walking distance of Twitter's in San Francisco.[60]

In September 2011, board members and investors Fred Wilson and Bijan Sabet resigned from Twitter's Board of Directors.[62]

In October 2012, Twitter announced it had hired Google executive Matt Derella to become their new director of business agency development.[63]
Logo

Twitter has become internationally identifiable by its signature bird logo. The original logo was in use from its launch in March 2006 until September 2010. A slightly modified version succeeded the first style when the website underwent its first redesign.

On February 27, 2012, a tweet from an employee that works on the company's platform and API discussed the evolution of the "Larry the Bird" logo with Twitter's creative director and it was revealed that it was named after Larry Bird of the NBA's Boston Celtics fame. This detail had previously been confirmed when the Boston Celtics' director of interactive media asked Twitter co-founder Biz Stone about it in August 2011.[64]

On June 5, 2012, Twitter unveiled its third logo redesign, replacing Larry the Bird with an updated icon simply named as the "Twitter Bird." As of this logo revision, the word "Twitter" and the lowercase letter "t" are no longer used, with the bird becoming the sole symbol for the company's branding.[65] According to Douglas Bowman, designer of Twitter, the new logo resembles a Mountain Bluebird.[66]

    The original logo, used from 15 July 2006 until 14 September 2010.

    The second logo, used from 14 September 2010 until 5 June 2012.

    The third and current logo, used since 5 June 2012.

Features
Tweets
The Twitter account page for Wikipedia, demonstrating the account-customized timeline view showing tweets in reverse chronological order

Tweets are publicly visible by default, but senders can restrict message delivery to just their followers. Users can tweet via the Twitter website, compatible external applications (such as for smartphones), or by Short Message Service (SMS) available in certain countries.[67] While the service is free, accessing it through SMS may incur phone service provider fees.[citation needed]

Users may subscribe to other users' tweets – this is known as following and subscribers are known as followers[68] or tweeps a portmanteau of Twitter and peeps.[69] The users can also check the people who are un-subscribing them on Twitter better known as unfollowing via various services.[70] In addition, users have the capability to block those who have followed them.

Twitter allows users the ability to update their profile by using their mobile phone either by text messaging or by apps released for certain smartphones and tablets.[71]

Twitter has been compared to a web-based Internet Relay Chat (IRC) client.[72] In a 2009 Time essay, technology author Steven Johnson described the basic mechanics of Twitter as "remarkably simple":[73]

    As a social network, Twitter revolves around the principle of followers. When you choose to follow another Twitter user, that user's tweets appear in reverse chronological order on your main Twitter page. If you follow 20 people, you'll see a mix of tweets scrolling down the page: breakfast-cereal updates, interesting new links, music recommendations, even musings on the future of education.

Content
Content of Tweets according to Pear Analytics
  News (3.6%)
  Spam (3.8%)
  Self-promotion (5.9%)
  Pointless babble (40.1%)
  Conversational (37.6%)
  Pass-along value (8.7%)

San Antonio-based market-research firm Pear Analytics analyzed 2,000 tweets (originating from the US and in English) over a two-week period in August 2009 from 11:00 AM to 5:00 PM (CST) and separated them into six categories:[74]

    Pointless babble – 40%
    Conversational – 38%
    Pass-along value – 9%
    Self-promotion – 6%
    Spam – 4%
    News – 4%

Social networking researcher danah boyd responded to the Pear Analytics survey by arguing that what the Pear researchers labelled "pointless babble" is better characterized as "social grooming" and/or "peripheral awareness" (which she explains as persons "want[ing] to know what the people around them are thinking and doing and feeling, even when co-presence isn’t viable").[75]
Format

Users can group posts together by topic or type by use of hashtags – words or phrases prefixed with a "#" sign. Similarly, the "@" sign followed by a username is used for mentioning or replying to other users.[76] To repost a message from another Twitter user, and share it with one's own followers, the retweet function is symbolized by "RT" in the message.[citation needed]

In late 2009, the "Twitter Lists" feature was added, making it possible for users to follow (as well as mention and reply to) ad-hoc lists of authors instead of individual authors.[68][77]

Through SMS, users can communicate with Twitter through five gateway numbers: short codes for the United States, Canada, India, New Zealand, and an Isle of Man-based number for international use. There is also a short code in the United Kingdom which is only accessible to those on the Vodafone, O2[78] and Orange[79] networks. In India, since Twitter only supports tweets from Bharti Airtel,[80] an alternative platform called smsTweet[81] was set up by a user to work on all networks.[82] A similar platform called GladlyCast[83] exists for mobile phone users in Singapore, Malaysia and the Philippines.[citation needed]

The tweets were initially set to a 140-character limit for compatibility with SMS messaging, introducing the shorthand notation and slang commonly used in SMS messages. The 140-character limit has also increased the usage of URL shortening services such as bit.ly, goo.gl, and tr.im, and content-hosting services, such as Twitpic, memozu.com and NotePub to accommodate multimedia content and text longer than 140 characters. Twitter uses its own t.co domain for automatic shortening of all URLs posted on its website.[84]
Trending topics

A word, phrase or topic that is tagged at a greater rate than other tags is said to be a trending topic. Trending topics become popular either through a concerted effort by users or because of an event that prompts people to talk about one specific topic.[85] These topics help Twitter and their users to understand what is happening in the world.[86]

Trending topics are sometimes the result of concerted efforts by fans of certain celebrities or cultural phenomena, particularly Lady Gaga (known as Monsters), Justin Bieber (Beliebers) and fans of the Twilight (Twihards) and Harry Potter (Potterheads) novels. Twitter have altered the trend algorithm in the past to prevent manipulation of this type.[87]

Twitter's March 30, 2010 blog post announced that the hottest Twitter trending topics would scroll across the Twitter homepage.[88]

There have been controversies surrounding Twitter trending topics: Twitter has censored hashtags that other users found offensive. Twitter censored the #Thatsafrican[89] and the #thingsdarkiessay[90] hashtags after users complained that they found the hashtags offensive.[citation needed]
Adding and following content

There are numerous tools for adding content, monitoring content and conversations including Twitvid (video sharing),[91] TweetDeck, Salesforce.com, HootSuite, and Twitterfeed. As of 2009, fewer than half of tweets were posted using the web user interface with most users using third-party applications (based on analysis of 500 million tweets by Sysomos).[92]
Verified accounts

In June 2008, Twitter launched a verification program, allowing celebrities to get their accounts verified.[93] Originally intended to help users verify which celebrity accounts were created by the celebrities themselves (and therefore are not fake), they have since been used to verify accounts of businesses and accounts for public figures who may not actually tweet but still wish to maintain control over the account that bears their name - for example, the Dalai Lama.
Mobile
The mobile version of Twitter, mobile.twitter.com

Twitter has mobile apps for iPhone, iPad, Android, Windows Phone, BlackBerry, and Nokia S40.[94] There is also version of the website for mobile devices as well as SMS and MMS service.[95] Twitter limits the use of 3rd party applications utilizing the service by implementing a 100,000 user limit.[96]
Authentication

As of August 31, 2010, third-party Twitter applications are required to use OAuth, an authentication method that does not require users to enter their password into the authenticating application. Previously, the OAuth authentication method was optional, it is now compulsory and the user-name/password authentication method has been made redundant and is no longer functional. Twitter stated that the move to OAuth will mean "increased security and a better experience".[97]
Usage
Rankings

Twitter is ranked as one of the ten-most-visited websites worldwide by Alexa's web traffic analysis.[98] Daily user estimates vary as the company does not publish statistics on active accounts. A February 2009 Compete.com blog entry ranked Twitter as the third most used social network based on their count of 6 million unique monthly visitors and 55 million monthly visits.[99] In March 2009, a Nielsen.com blog ranked Twitter as the fastest-growing website in the Member Communities category for February 2009. Twitter had annual growth of 1,382 percent, increasing from 475,000 unique visitors in February 2008 to 7 million in February 2009.[100] In 2009, Twitter had a monthly user retention rate of forty percent.[101]
Demographics
Twitter.com Top5 Global Markets by Reach (%)[102][103]
Country             Percent    
Indonesia     Jun 2010    
  
    20.8%    
Dec 2010    
  
    19.0%
Brazil     Jun 2010    
  
    20.5%    
Dec 2010    
  
    21.8%
Venezuela     Jun 2010    
  
    19.0%    
Dec 2010    
  
    21.1%
Netherlands     Jun 2010    
  
    17.7%    
Dec 2010    
  
    22.3%
Japan     Jun 2010    
  
    16.8%    
Dec 2010    
  
    20.0%
Note: Visitor age 15+, home and work locations. Excludes visitation from public computers such as Internet cafes or access from mobile phones or PDAs.

In 2009, Twitter was mainly used by older adults who might not have used other social sites before Twitter, said Jeremiah Owyang, an industry analyst studying social media. "Adults are just catching up to what teens have been doing for years," he said.[104] According to comScore only eleven percent of Twitter's users are aged twelve to seventeen.[104] comScore attributed this to Twitter's "early adopter period" when the social network first gained popularity in business settings and news outlets attracting primarily older users. However, comScore also stated in 2009 that Twitter had begun to "filter more into the mainstream", and "along with it came a culture of celebrity as Shaq, Britney Spears and Ashton Kutcher joined the ranks of the Twitterati."[105]

According to a study by Sysomos in June 2009, women make up a slightly larger Twitter demographic than men — fifty-three percent over forty-seven percent. It also stated that five percent of users accounted for seventy-five percent of all activity, and that New York City has more Twitter users than other cities.[106]

According to Quancast, twenty-seven million people in the US used Twitter as of September 3, 2009. Sixty-three percent of Twitter users are under thirty-five years old; sixty percent of Twitter users are Caucasian, but a higher than average (compared to other Internet properties) are African American/black (sixteen percent) and Hispanic (eleven percent); fifty-eight percent of Twitter users have a total household income of at least US$60,000.[107] The prevalence of African American Twitter usage and in many popular hashtags has been the subject of research studies.[108][109]

On September 7, 2011, Twitter announced that it has 100 million active users logging in at least once a month and 50 million active users every day.[110]

In an article published on January 6, 2012, Twitter was confirmed to be the biggest social media network in Japan, with Facebook following closely in second. comScore confirmed this, stating that Japan is the only country in the world where Twitter leads Facebook.[111]
Finances
Funding
Twitter's San Francisco headquarters located at 1355 Market St.

Twitter raised over US$57 million from venture capitalist growth funding, although exact numbers are not publicly disclosed. Twitter's first A round of funding was for an undisclosed amount that is rumored to have been between US$1 million and US$5 million.[112] Its second B round of funding in 2008 was for US$22 million[113] and its third C round of funding in 2009 was for US$35 million from Institutional Venture Partners and Benchmark Capital along with an undisclosed amount from other investors including Union Square Ventures, Spark Capital and Insight Venture Partners.[112] Twitter is backed by Union Square Ventures, Digital Garage, Spark Capital, and Bezos Expeditions.[114]

In May 2008, The Industry Standard remarked that Twitter's long-term viability is limited by a lack of revenue.[115] Twitter board member Todd Chaffee forecast that the company could profit from e-commerce, noting that users may want to buy items directly from Twitter since it already provides product recommendations and promotions.[116]

The company raised US$200 million in new venture capital in December 2010, at a valuation of approximately US$3.7 billion.[117] In March 2011, 35,000 Twitter shares sold for US$34.50 each on Sharespost, an implied valuation of US$7.8 billion.[118] In August, 2010 Twitter announced a "significant" investment lead by Digital Sky Technologies that, at US$800 million, was reported to be the largest venture round in history.[119]

Twitter has been identified as a possible candidate for an initial public offering by 2013.[120]

In December 2011, the Saudi prince Alwaleed bin Talal invested $300 million in Twitter. The company was valued at $8.4 billion at the time.[121]
Revenue sources

In July 2009, some of Twitter's revenue and user growth documents were published on TechCrunch after being illegally obtained by Hacker Croll. The documents projected 2009 revenues of US$400,000 in the third quarter and US$4 million in the fourth quarter along with 25 million users by the end of the year. The projections for the end of 2013 were US$1.54 billion in revenue, US$111 million in net earnings, and 1 billion users.[3] No information about how Twitter planned to achieve those numbers was published. In response, Twitter co-founder Biz Stone published a blog post suggesting the possibility of legal action against the hacker.[122]

On April 13, 2010, Twitter announced plans to offer paid advertising for companies that would be able to purchase "promoted tweets" to appear in selective search results on the Twitter website, similar to Google Adwords' advertising model. As of April 13, Twitter announced it had already signed up a number of companies wishing to advertise including Sony Pictures, Red Bull, Best Buy, and Starbucks.[123][124]

To continue their advertising campaign, Twitter announced on March 20, 2012, that it would be bringing its promoted tweets to mobile devices. Twitter generated US$139.5 million in advertising sales during 2011 and expects this number to grow 86.3% to US$259.9 million in 2012.[125]

The company generated US$45 million in annual revenue in 2010, after beginning sales midway through that year. The company operated at a loss through most of 2010. Revenues were forecast for US$100 million to US$110 million in 2011.[117] Users' photos can generate royalty-free revenue for Twitter, with an agreement with WENN being announced in May 2011.[126] In June 2011, Twitter announced that it would offer small businesses a self serve advertising system.[127]
Technology
Implementation

Great reliance is placed on open-source software.[128] The Twitter Web interface uses the Ruby on Rails framework,[129] deployed on a performance enhanced Ruby Enterprise Edition implementation of Ruby.[130]

As of April 6, 2011, Twitter engineers confirmed they had switched away from their Ruby on Rails search-stack, to a Java server they call Blender.[6]

From spring 2007 to 2008 the messages were handled by a Ruby persistent queue server called Starling,[131] but since 2009 implementation has been gradually replaced with software written in Scala.[132] The service's application programming interface (API) allows other web services and applications to integrate with Twitter.[133][134]

Individual tweets are registered under unique IDs using software called snowflake and geolocation data is added using 'Rockdove'. The URL shortner t.co then checks for a spam link and shortens the URL. The tweets are stored in a MySQL database using Gizzard and acknowledged to users as having been sent. They are then sent to search engines via the Firehose API. The process itself is managed by FlockDB and takes an average of 350 ms.[128]
Interface

On April 30, 2009, Twitter adjusted its web interface, adding a search bar and a sidebar of "trending topics" — the most common phrases appearing in messages. Biz Stone explains that all messages are instantly indexed and that "with this newly launched feature, Twitter has become something unexpectedly important – a discovery engine for finding out what is happening right now."[135]

In March 2012, Twitter became available in Arabic, Farsi, Hebrew and Urdu, the first right-to-left language versions of the site. About 13,000 volunteers helped with translating the menu options.[136] In August 2012, beta support for Basque, Czech and Greek was added, making the site available in 33 different languages.[137]
Outages
The Twitter fail whale error message.

When Twitter experiences an outage, users see the "fail whale" error message image created by Yiying Lu,[138] illustrating eight orange birds using a net to hoist a whale from the ocean captioned "Too many tweets! Please wait a moment and try again."[139]

Twitter had approximately ninety-eight percent uptime in 2007 (or about six full days of downtime).[140] The downtime was particularly noticeable during events popular with the technology industry such as the 2008 Macworld Conference & Expo keynote address.[141][142]

    May 2008 – Twitter's new engineering team made architectural changes to deal with the scale of growth. Stability issues resulted in down time or temporary feature removal.
    August 2008 – Twitter withdrew free SMS services from users in the United Kingdom[143] and for approximately five months instant messaging support via a XMPP bot was listed as being "temporarily unavailable".[144]
    October 10, 2008 – Twitter's status blog announced that instant messaging (IM) service was no longer a temporary outage and needed to be revamped. It was announced that Twitter aims to return its IM service pending necessary major work.[145]
    June 12, 2009 – In what was called a potential "Twitpocalypse", the unique numerical identifier associated with each tweet exceeded the limit of 32-bit signed integers (2,147,483,647 total messages).[146] While Twitter itself was not affected, some third-party clients could no longer access recent tweets. Patches were quickly released, though some iPhone applications had to wait for approval from the App Store.[147]
    June 25, 2009 – Twitter ran slowly for some time after over 50,000 tweets on Michael Jackson’s death were recorded in an hour.[148]
    August 6, 2009 – Twitter and Facebook suffered from a denial-of-service attack, causing the Twitter website to go offline for several hours.[149] It was later confirmed that the attacks were directed at one pro-Georgian user around the anniversary of the 2008 South Ossetia War, rather than the sites themselves.[150]
    September 22, 2009 – The identifier exceeded the limit for 32-bit unsigned integers (4,294,967,296 total messages) again breaking some third-party clients.[151]
    December 17, 2009 – A hacking attack replaced the website's welcoming screen with an image of a green flag and the caption "This site has been hacked by Iranian Cyber Army" for nearly an hour. No connection between the hackers and Iran has been established.[152]
    June–July 2010 – Twitter had a very high service rejection rate (10–20%) during the 2010 FIFA World Cup period, also, the response latency increased substantially.[153]
    November 2010 – A number of accounts encountered a fault that resulted in them seeing the "fail whale" when they tried to login to their accounts. The accounts themselves were not locked out as account holders could still see their "mentions" page, and post from there, but the timeline and a number of other features were unavailable during this outage.
    June 21, 2012 – The site was down for around one hour and forty minutes, with the cause being described by Twitter as a "cascading bug".[154]
    July 26, 2012 – Twitter users in the UK could not post messages for part of the day in advance of the 2012 Summer Olympics.[155]

Privacy and security

Twitter messages are public but users can also send private messages.[156] Twitter collects personally identifiable information about its users and shares it with third parties. The service reserves the right to sell this information as an asset if the company changes hands.[157] While Twitter displays no advertising, advertisers can target users based on their history of tweets and may quote tweets in ads[158] directed specifically to the user.

A security vulnerability was reported on April 7, 2007, by Nitesh Dhanjani and Rujith. Since Twitter used the phone number of the sender of an SMS message as authentication, malicious users could update someone else's status page by using SMS spoofing.[159] The vulnerability could be used if the spoofer knew the phone number registered to their victim's account. Within a few weeks of this discovery Twitter introduced an optional personal identification number (PIN) that its users could use to authenticate their SMS-originating messages.[160]

On January 5, 2009, 33 high-profile Twitter accounts were compromised after a Twitter administrator's password was guessed by a dictionary attack.[161] Falsified tweets — including sexually explicit and drug-related messages — were sent from these accounts.[162]

Twitter launched the beta version of their "Verified Accounts" service on June 11, 2009, allowing famous or notable people to announce their Twitter account name. The home pages of these accounts display a badge indicating their status.[163]

In May 2010, a bug was discovered by İnci Sözlük, involving users that allowed Twitter users to force others to follow them without the other users' consent or knowledge. For example, comedian Conan O'Brien's account, which had been set to follow only one person, was changed to receive nearly 200 malicious subscriptions.[164]

In response to Twitter's security breaches, the US Federal Trade Commission brought charges against the service which were settled on June 24, 2010. This was the first time the FTC had taken action against a social network for security lapses. The settlement requires Twitter to take a number of steps to secure users' private information, including maintenance of a "comprehensive information security program" to be independently audited biannually.[165]

On December 14, 2010, the United States Department of Justice issued a subpoena directing Twitter to provide information for accounts registered to or associated with WikiLeaks.[166] Twitter decided to notify its users and said in a statement, "...it's our policy to notify users about law enforcement and governmental requests for their information, unless we are prevented by law from doing so".[156]

A "MouseOver" exploit occurred on September 21, 2010, when an XSS Worm became active on Twitter. When an account user held the mouse cursor over blacked-out parts of a tweet, the worm within the script would automatically open links and re-post itself on the reader's account.[167] The exploit was then re-used to post pop-up ads and links to pornographic sites. The origin is unclear but Pearce H. Delphin (known on Twitter as @zzap) and a Scandinavian developer, Magnus Holm, both claim to have modified the exploit of a user, possibly Masato Kinugawa, who was using it to create coloured Tweets.[168] Kinugawa, a Japanese developer, reported the XSS vulnerability to Twitter on August 14. Later, when he found it was exploitable again, he created the account 'RainbowTwtr' and used it to post coloured messages.[168] Delphin says he exposed the security flaw by tweeting a JavaScript function for "onMouseOver",[168] and Holm later created and posted the XSS Worm that automatically re-tweeted itself.[167] Security firm Sophos reported that the virus was spread by people doing it for "fun and games", but noted it could be exploited by cybercriminals.[167] Twitter issued a statement on their status blog at 13:50 UTC that "The exploit is fully patched". Twitter representative Carolyn Penner said no charges would be pressed.[170]

In May 2011, a claimant known as "CTB" (subsequently identified as Ryan Giggs) in the case of CTB v Twitter Inc., Persons Unknown took legal action at the High Court of Justice in London against Twitter.,[171] requesting that Twitter release details of account holders. This followed gossip posted on Twitter about Giggs' private life, causing conflict relating to privacy injunctions.[172][173] Tony Wang, the head of Twitter in Europe, said that people who do "bad things" on the site would need to defend themselves under the laws of their own jurisdiction in the event of controversy, and that the site would hand over information about users to the authorities when it was legally required to do so.[174] He also suggested that Twitter would accede to a UK court order to divulge names of users responsible for "illegal activity" on the site.[175]

On May 29, 2011, it was reported that South Tyneside council in England had successfully taken legal action against Twitter in a court in California, which forced Twitter to reveal the details of five user accounts. The council was trying to discover the identity of a blogger called "Mr Monkey"[176] who allegedly posted libellous statements about three local councillors.[177]

On January 23, 2012, it was reported that Twitter would be acquiring Dasient, a startup that offers malware protection for businesses. Twitter hopes that Dasient will help remove hateful advertisers on the website.[178]

On January 26, 2012, Twitter began offering a feature which would allow tweets to be removed selectively by country. Twitter cited France and Germany as examples, where pro-Nazi content is illegal. Previously, deleted tweets were removed in all countries.[179][180] The first use of the policy was to block the account of German neo-Nazi group Besseres Hannover on October 18, 2012.[181] The policy was used again the following day to remove anti-Semitic French tweets with the hashtag #unbonjuif ("a good jew").[182]

On February 20, 2012, a third-party public-key encryption app (written in Python and partially funded by a grant from the Shuttleworth Foundation[183]) for private messaging in Twitter, CrypTweet, was released.[184]

On May 17, 2012, Twitter announced it would implement the "Do Not Track" privacy option, a cookie-blocking feature found in Mozilla's Firefox browser. The "Do Not Track" feature works only on sites that have agreed to the service.[185]

In August 2012 it was reported that there is a market in fake Twitter followers that are used to increase politicians' and celebrities' apparent popularity.[186]
Open source

Twitter released several open source projects developed while overcoming technical challenges of their service.[187] Notable projects are the Gizzard Scala framework for creating distributed datastores and the distributed graph database FlockDB.
Innovators patent agreement

On April 17, 2012, Twitter announced it would implement an “Innovators Patent Agreement” which would obligate Twitter to only use its patents for defensive purposes. The agreement will go into effect later 2012.[188]

URL shortener

t.co is a URL shortening service created by Twitter.[84] It is only available for links posted to Twitter and not available for general use.[84] All links posted to Twitter use a t.co wrapper.[189] Twitter hopes that the service will be able to protect users from malicious sites,[84] and will use it to track clicks on links within tweets.[84][190]

Having previously used the services of third parties TinyURL and bit.ly,[191] Twitter began experimenting with its own URL shortening service for private messages in March 2010 using the twt.tl domain,[189] before it purchased the t.co domain. The service was tested on the main site using the accounts @TwitterAPI, @rsarver and @raffi.[189] On September 2, 2010, an email from Twitter to users said they would be expanding the roll-out of the service to users. On June 7, 2011, Twitter announced that it was rolling out the feature.[192]
Integrated photo-sharing service

On June 1, 2011, Twitter announced its own integrated photo-sharing service that enables users to upload a photo and attach it to a Tweet right from Twitter.com.[193] Users now also have the ability to add pictures to Twitter's search by adding hashtags to the tweet.[194] Twitter also plans to provide photo galleries designed to gather and syndicate all photos that a user has uploaded on Twitter and third-party services such as TwitPic.