RISC

Reduced Instruction Set Computers (RISC) have a small number of instructions. The idea of RISC is that it is better to have a small, sleek, fast instruction set than to have a big collection of poorly coordinated, ungainly, complex instructions.

If a small set of instructions is implemented on a chip, the chip now has room for more general purpose registers, a larger on-chip memory cache, an instruction pipeline, and other features that add speed.

For the last decade or so RISC chips have been ahead of CISC chips. But modern CISC chips now include many of the features of RISC chips (such as cache and pipelining). Modern CISC chips have greater throughput than older RISC chips. Consumer and office computers use CISC chips to be compatible with existing Windows software. High-end workstations and recently designed systems (such as embedded systems) typically use RISC.