Ceramic clutch - Ceramic is the friction material the clutch is made of, usually found on uprated street discs.
6 puk - 6 Puk is a type of clutch with 6 paddles with 6 individual friction pads on the end of each puk.
4 puk - 4 Puk is the same as a 6 puck but with 4 paddles.
Sprung - Sprung clutches have springs built in designed to absorb the shock of engagement making for a smoother gear change.
Unsprung - Unsprung is the opposite of above and usually paired with a dual mass flywheel. The stock setup uses this design.
Dual mass flywheels - A Dual Mass Flywheel is basically two components linked together by a damping mechanism within the secondary mass and located by the central carrier bearing. The damping mechanism is there to absorb the torque loads of the crankshaft and to help deliver a smooth transfer to the road wheels. It also dampens noise and vibration which is why when you replace the stock dual mass flywheel with a light weight version the transmission sounds like marbles rattling in a can. That's actually the transmission which makes that noise.