Public transport, public transportation, public transit or mass transit comprise all transport systems that transport members of the general public, usually charging set fares. While the above terms are generally taken to include rail and bus services, wider definitions might include scheduled airline services, ferries, taxicab services etc. A further restriction that is sometimes applied is that transit should occur in continuously shared vehicles, which would exclude taxis that are not shared-ride taxis.

Public transport is usually regulated as a common carrier and is usually configured to provide scheduled service on fixed routes on a non-reservation basis, although share taxis provide an ad-hoc form of flexible public transport, and demand responsive transport provides a pre-bookable form of public shared transport. Taxicabs and other vehicles for hire are generally fully flexible.

The majority of transit passengers are traveling within a local area or region between their homes and places of employment, shopping, or schools.

In many parts of the world private transport dominates; however, in places with public transport systems, and where private transport use is not practical or not affordable, or where the public transport is more practical or more desirable than the private alternatives, then it is used. Many towns and cities around the world are investing in public transport initiatives to increase the attractiveness and usage of public transport.

Public transport can offer significant advantages in areas with higher population densities if it is efficiently utilised, due to its potentially smaller physical and environmental footprint per passenger.

Road-based public transport risks being slower than private vehicles if it gets held up in general traffic congestion. Compounding upon this, scheduled transport vehicles have to make frequent stops to board additional passengers, and an individual trip may require one or more transfers. Routes are also often circuitous to increase the area serviced by the system. Therefore, transport authorities wishing to increase the attractiveness and use of public transport often respond by establishing or expanding dedicated or semi-dedicated public transport lanes, traffic signal priority, and other measures.

The term rapid transit, is often used to distinguish modes of transit possessing a dedicated right of way and having frequent, continuous service. Still, rapid transit often fails to live up to the name, as there are no firm guidelines as to how fast transit must be to be rapid.[1] Light rail is another form of public transit, comprising of a tram or trolley operating on a rail line.

A popular public transport mode in the developing world, and increasingly in the western world, is the share taxi (mini-bus, jitney etc) that run on flexible or semi-flexible routes.

Transport Interchanges

Of critical importance to attractive and successful public transport is the design of the transport interchanges where people access the system and interchange between different vehicles. These transport interchanges range for extensive multi-modal interchanges such as found at major airports to the humble bus stop.