Personal rapid transit (PRT), or podcar, is a model of public transport which strives to combine the efficiencies of mass transit with much of the convenience of taxis or private vehicles. The vehicles are small and driverless, running on "guideways" (generally some form of rail). Typically PRT vehicles are avilable on demand and travel non-stop to their destination station. Stations are off-line (on sidings) allowing other vehicles to by pass them without stopping. Wait times are typicaly under a minute (at the Heathrow Airport system, 70% of riders are met by a vehicle in the station and have no wait at all).
The idea was explored and promoted intensively in the 1960's and 1970's, but the required technology may become more reliable and cost-effective in the early 21st century. Until recently, the only operational PRT in the world was Morgantown Personal Rapid Transit,W which opened in 1975. A modern PRT system entered public service in Masdar City, UAE in 2010. Another commenced 22/7 service at Heathrow Airport, UK in April 2011.