RISC (reduced instruction set computer)

In the mid-1980s to early-1990s, a crop of new high-performance RISC microprocessors appeared, which were initially used in special purpose machines and UNIX workstations, but have since become almost universal in all roles except the Intel-standard desktop.

The first commercial design was released by MIPS Technologies, the 32-bit R2000. The R3000 made the design truly practical, and the R4000 introduced the world's first 64-bit design. Opposing projects would result in the IBM POWER and Sun SPARC systems, respectively. Soon every major vendor was releasing a RISC design, including the AT&T CRISP, AMD 29000, Intel i860 and Intel i960, Motorola 88000, DEC Alpha and the HP-PA.

Market forces have "weeded out" many of these designs, leaving the PowerPC as the main desktop RISC processor, with the SPARC being used in Sun designs only. MIPS continue to supply some SGI systems, but are first and foremost used as an embedded design, notably in Cisco routers. The rest of the original crop of designs have either disappeared, or are about to. Other companies have attacked niches in the market, notably ARM, originally intended for home computer use but since focused at the embedded processor market. Today RISC designs based on the MIPS, ARM or PowerPC core are the vast majority of computing devices.