The term as used in Great Britain is trades union (plural: "trades unions") because they were a joining of men "working in different trades". For example: on the engine of a steam locomotive were two men: a driver and a stoker shovelling the coal into the oven. The driver was a skilled man, and paid much more than the stoker. They were two different trades. When they joined into the Associated Society of Locomotive Engineers and Firemen (ASLEF), their negotiations with management was done together. A quite different union, the National Union of Railwaymen (NUR) looked after other employees of the railway compaies. That was a whole collection of different trades.