What is the purpose of a drum machine?

Question

Also who mainly uses them

Answer 1

It makes it easier to produce music that would normally require "actual talent" the Rap/R&B and techno industry use them to death.

Answer 2

It's a synthesizer and sequencer that allows you to program drum lines for the percussion track of your music. A sequencer is a timer that triggers a sound, in this case sampled drums and cymbals.

You would either use a preprogrammed drum beat (like boom-whack-ka-boom-boom-whack) or you can program it manually to provide fills or other effects.

You can either use it as a kind of metronome for practicing other instruments or, as someone else pointed out, lots of pop and rap bands use - or rather overuse - them as the main percussion track in their music.