What are the different types of bicycle rear hub types available in the market?

The different types of bicycle rear hub types available in the market include freewheel hubs, cassette hubs, and coaster brake hubs. Freewheel hubs have the freewheel mechanism built into the hub, while cassette hubs have the freewheel mechanism built into the cassette. Coaster brake hubs have a brake mechanism built into the hub that is activated by pedaling backward.