Reduced instruction-set computer

Meaning – The term reduced instruction-set computer, or RISC, refers to a computer that uses a small, simplified set of frequently used instructions for rapid execution.

The main distinguishing feature of RISC architecture is that the instruction set is optimized with a large number of registers and a highly regular instruction pipeline, allowing a low number of clock cycles per instruction (CPI).

With RISC, the basic concept is to have simple instructions that do less but execute very quickly to provide better performance.

RISC processors require fewer cycles per second than CISC processors. A RISC processor may complete more operations per second than a CISC processor running at the same clock speed.

Example of usage“The words “reduced instruction set” are often misinterpreted to refer to a reduced number of instructions. However, this is not the case, as several RISC processors, like the PowerPC, have numerous instructions. At the opposite end of the spectrum, the DEC PDP-8, a CISC CPU, has only eight basic instructions.”