The SFMTA plans, designs, builds, operates, regulates, and maintains one of the most diverse transportation networks in the world. In addition to the four modes of transportation (transit, walking, bicycling and driving, which includes private vehicles, taxis, carsharing, on-and off-street parking and commercial vehicles), the Agency directly oversees five transit modes (bus, trolley bus, light rail, historic streetcar, and cable car), in addition to overseeing paratransit service, which serves individuals unable to use fixed-route transit service.