For cars,I would say there are the 2 basic categories.
Competitive RC car racing(guys doing this are called as 'racers' or 'rc car racers' or 'model car racers.')
and
casual driving(referred to as "bashing" among car guys).(Guys who do this are typically known as "bashers")
Once you go into the intricacies of racing,you see classes first.Usually 1/12(typically on-road stuff),1/10(on-road and off-road),1/8(on road and off road) and 1/5(on road and off road).Then,you have dirt oval racing and rock crawling and drifting.These are the basic classes.
Hope this answers a part of your question.