The United States is serviced by a wide array of public transportation, including various forms of bus, rail, ferry, and sometimes, airline services. Most established public transit systems are located in central, urban areas where there is enough density and public demand to require public transportation.[1] In more auto-centric suburban localities, public transit is normally, but not always, less frequent and less common. Most public transit services in the United States are either national, regional/commuter, or local, depending on the type of service. Sometimes "public transportation" in the United States is an umbrella term used synonymously with "alternative transportation", meaning any form of mobility that excludes driving alone by automobile.[2] This can sometimes include carpooling,[3]vanpooling,[4] on-demand mobility (i.e. Uber, Lyft, Bird, Lime),[5] infrastructure that is oriented toward bicycles (i.e. bike lanes, sharrows, cycle tracks, and bike trails),[6] and paratransit service.[7] There is public transit service in most US cities.
^Haring, Joseph E.; Slobko, Thomas; Chapman, Jeffrey (January 1976). "The impact of alternative transportation systems on urban structure". Journal of Urban Economics. 3: 14–30. doi:10.1016/0094-1190(76)90055-3.
^Correia, Gonçalo; Viegas, José Manuel (2011-02-01). "Carpooling and carpool clubs: Clarifying concepts and assessing value enhancement possibilities through a Stated Preference web survey in Lisbon, Portugal". Transportation Research Part A: Policy and Practice. 45 (2): 81–90. doi:10.1016/j.tra.2010.11.001. ISSN0965-8564.
^Bush, Leon R. Vanpool Implementation in Los Angeles: Commute-a-van. Aerospace Corporation, 1975.
^Pavone, Marco; Morton, Daniel; Frazzoli, Emilio; Zhang, Rick; Treleaven, Kyle; Spieser, Kevin (2014), "Toward a Systematic Approach to the Design and Evaluation of Automated Mobility-on-Demand Systems: A Case Study in Singapore", Road Vehicle Automation, Lecture Notes in Mobility, Springer, Cham, pp. 229–245, doi:10.1007/978-3-319-05990-7_20, hdl:1721.1/82904, ISBN9783319059891