RISC

RISC
Reduced instruction set computing, or RISC  is a CPU design strategy based on the insight that simplified (as opposed to complex) instructions can provide higher performance if this simplicity enables much faster execution of each instruction.
A computer based on this strategy is a reduced instruction set computer, also called RISC.
The opposing architecture is known as complex instruction set computing, i.e. CISC.

Well known RISC families include DEC Alpha, AMD 29k, ARC, ARM, Atmel AVR, Blackfin, Intel i860 and i960, MIPS, Motorola 88000, PA-RISC, Power (including PowerPC), SuperH, and SPARC
http://en.wikipedia.org/wiki/Reduced_instruction_set_computing