PowerPC (short for Performance Optimization With Enhanced RISC – Performance Computing, sometimes abbreviated as PPC) is a RISC architecture created by the 1991 Apple–IBM–Motorola alliance, known as AIM. PowerPC, as an evolving instruction set, has since 2006 been renamed Power ISA but lives on as a legacy trademark for some implementations of Power Architecture based processors.
Originally intended for personal computers, PowerPC CPUs have since become popular as embedded and high-performance processors. PowerPC was the cornerstone of AIM's PReP and Common Hardware Reference Platform initiatives in the 1990s and while the architecture is well known for being used by Apple's Macintosh lines from 1994 to 2006 (before Apple's transition to Intel), its use in video game consoles and embedded applications provided an array of uses.
PowerPC is largely based on IBM's earlier POWER architecture, and retains a high level of compatibility with it; the architectures have remained close enough that the same programs and operating systems will run on both if some care is taken in preparation; newer chips in the POWER series implement the full PowerPC instruction set.
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