Original: A drum set (also drum kit or trap set) is a collection of drums, cymbals and sometimes other percussion instruments, such as cowbells, wood blocks, triangles, chimes, or tambourines, arranged for convenient playing by a single person (drummer).
Simplified: A drum kit (or drum set or trap set) is a collection of drums, cymbals, and other percussion instruments that is used by a drummer in a musical group.