British electric multiple units
An electric multiple unit (EMU) is an electric self-powered train, capable of operating in multiple with other EMUs and without the need for a locomotive; these are typically passenger trains with accommodation in every vehicle and a driving position at each end. The term can also be used to describe a train that is a permanent formation with a non-driving power car, such as the Advanced Passenger Train.
Source: Wikipedia — British electric multiple units (CC BY-SA 4.0)