Surely:
Cassette: the multiple sprockets of different sizes attached to your back wheel. the smallest one makes you go fastest for a given cadence, the largest one makes you slowest for a given cadence. The idea is to maintain a constant cadence over different terrain, changing up and down the cassetee as required.
Chainrings: the two or three large sprockets attached to your cranks. The bigger/est one makes you faster/est for a given cadence. The idea is to maintain constant cadence over different terrain, changing up and down the chainrings as required
Front derailleur: a device for moving the chain between chainrings
Rear derailleur: a device for moving the chain between the sprockets of your cassette.
Chain: the oily bit that connects the chainrings to the cassette.