
A bicycle sharing system, or bike share scheme, is a service in which bicycles are made available for shared use to individuals on a very short term basis. The main purpose is transportation: bike share allows people to depart from point “A” and arrive at point “B” free from the worries of ownership.

Helsinki city bikes
Bike-share has seen explosive, global growth over recent years. As of April 2013 there were around 535 bike-sharing programmes around the world, made of an estimated fleet of 517,000 bicycles. In May 2011 there were around 375 schemes comprising 236,000 bikes So those two years saw a doubling of bike share globally.

Vélo’v in Lyon
Many bike-share systems offer subscriptions that make the first 30–45 minutes of use very inexpensive, encouraging their use as transportation. In most bike-share cities, people seeking a bicycle for casual riding over several hours or days are better served by bicycle rental than by bike-share.

Stockholm City Bikes, Sweden
Bike-share use is made more predictable with Smartphone mapping apps which show where nearby stations are located and how many bikes are available at each station. This is also important for riders looking to return a bike; they need to know if there is a dock open at a certain station, since stations can fill up with bikes. So using bike-share to get around a city is made far easier with real-time, GPS-based smartphone apps with bike-share station information overlaid on a city map.

Most of the latest systems use advanced information technologies (IT) for bicycle reservations, pick-up, drop-off, and information tracking.
The reasons people use bike-share vary considerably. In some cities, people who might use their own bicycle as transportation don’t do so because of concerns about theft or vandalism. In addition, many bike-share users find bike-share extremely liberating. A rider can seamlessly transfer to public transit or to a car without concern about leaving a bike behind: a person can ride to meet someone in a city, leave the bike-share bike then walk with them, tourists go from hotel to museum to show, citizens can take visiting friends or family to local attractions with bike-share, users may take public transit to work on a rainy day then ride home afterwards when the weather improves… the flexibility of not having to always park and own a bicycle make life freer and easier for the growing number of bike-share users globally.
The Wuhan and Hangzhou Public Bicycle bike-share programmes in China are the largest in the world, with around 90,000 and 60,000 bicycles respectively. In Hangzhou there are over 2,400 stations. The Vélib’ in Paris, which comprises around 20,000 bicycles and 1,450 bicycle stations, is the largest outside of China. The countries with the most systems are Spain (132), Italy (104), and China (79). The systems with the higher market penetration are both operating in France, the Parisian Velib’ with 1 bike per 97 inhabitants and Vélo’v in Lyon with 1 bike per 121 residents.
Bicycle sharing systems can be divided into two general categories: “Community Bike programmes” organised mostly by local community groups or non-profit organisations; and “Smart Bike programmes” implemented by government agencies, sometimes in a public-private partnership. The central concept of these systems is to provide free or affordable access to bicycles for short-distance trips in an urban area as an alternative to motorised public transport or private vehicles, thereby reducing traffic congestion, noise, and air pollution. Bicycle sharing systems have also been cited as a way to solve the “last mile” problem and connect users to public transit networks.

BikeMi, Milan, Italy
Public bike sharing programmes address some of the primary disadvantages to bicycle ownership, including loss from theft or vandalism, lack of parking or storage, and maintenance requirements. However, by limiting the number of places where bicycles can be rented or returned, the service itself essentially becomes a form of public transit, and has therefore been criticised as less convenient than a privately owned bicycle capable of point-to-point transport. Government-run bicycle sharing programmes can also prove costly to the public unless subsidised by commercial interests, typically in the form of advertising on stations or the bicycles themselves.

Boston’s Hubway is one of the first and largest bikeshare programs in the U.S.
Bike-sharing systems have undergone changes which can be categorised into three key phases, or generations. These include the first generation, called white bikes (or free bikes); the second generation of coin-deposit systems; and the third generation, or information technology(IT) based systems. Recent technological and operational improvements are also paving the way for a fourth generation, known as the demand-responsive, multimodal system.
List of Current bicycle sharing systems around the world (click on the link to know more)

The Hangzhou Public Bicycle programme in China, the second largest bicycle sharing system in the world

The Vélib’ in Paris is the largest bikesharing programme outside of China

White bicycles for free use, in Hoge Veluwe national park, the Netherlands

Bicycle station powered by solar panels

Citi Bike opened in New York City in May 2013 and is the largest bike sharing program in the U.S.

Solar powered Boulder B-cycle station with double sided docks.

Capital Bikeshare was launched in Washington, D.C. and Arlington County, Virginia in 2010

Bixi Montreal, Canada

Bicing in Barcelona

Velib’ bicycle station in Paris

A station in Lausanne (Switzerland).

Barclays Cycle Hire, London, UK started in 2010

The EBI in Esztergom, Hungary

VeloBike bicycles in Moscow, September 2013

Capital Bikeshare services Washington, D.C., Arlington, Virginia and Alexandria, Virginia

Bike Rio rental station located near Posto 9, Ipanema, in Rio de Janeiro city, Brazil.

A bicycle sharing station in Swanston Street, Melbourne.
Courtesy : Wikipedia