The coaster brake and band brake.
The coaster brake:
This is a special kind of brake..Almost on city bike.This brake function is braking when you back riding.The effect is fast and sudden.So must know how to control the speed.Some country are popular for this brake.It is look nice,cheaper and simple.But some are not.
The band brake:
A another style to be the rear brake. Children bike use many this brake.The effect is very compact. Mainly inside.The surface is not nicer than coaster brake.But also have the advantage.