A transit system encompasses all the vehicles, routes, stations, and operations that together provide public transportation within an area. Transit systems may include buses, subways, light rail, commuter rail, ferries, and specialized services like paratransit. System design involves route networks connecting where people live to where they work, shop, and access services. Effective systems provide frequent service on key corridors, reliable schedules, comfortable vehicles, and seamless transfers. System components must work together—timetables coordinate for connections, fare systems work across modes, and information systems provide comprehensive trip planning. Transit systems range from small municipal bus services to large multi-modal systems serving metropolitan regions. System quality significantly affects community mobility and transportation equity.