What are the differences between NMOS and PMOS transistors?

NMOS (N-channel MOSFET) uses electrons as carriers, has n-type source/drain in p-type substrate, turns on with positive gate voltage (Vgs > Vth), and passes strong 0 but weak 1. PMOS (P-channel MOSFET) uses holes as carriers, has p-type source/drain in n-well, turns on with negative gate voltage (Vgs < Vth), and passes strong 1 but weak 0. NMOS is faster (higher electron mobility) but both are combined in CMOS for complementary operation with low static power.