Bi-directional vehicle

Source: Wikipedia, the free encyclopedia.
route 5 of the Amsterdam tram network
are bi-directional vehicles. Notice the doors on the opposite side of the normal travel direction.
apron bus
, converted to an ambulance

A bi-directional vehicle is a

rail vehicles, such as trains or trams, and some airside transfer buses, that are equipped with driver's cabs at both ends. These vehicles generally have entry and exit doors
on either side of the vehicle.

One major benefit of bi-directional vehicles is the ability to reverse direction at a

turntable
to reverse direction.

Aside from eliminating the need for complicated railway infrastructure to turn vehicles around, the presence of doors on either side of the vehicle enable the use of island platforms. These extra doors come at the cost of reduction of seating on board the vehicle.