ARM, originally called ‘Acorn RISC Machine’ is a set of RISC (Reduced Instruction Set Computing) CPU architectures. ARM designs are highly flexible and can be configured for a wide range of use-cases. ARM Holdings, originally a UK company, develops the technology and licenses it to other corporations.
There are two ways to make an ARM CPU.
- License a reference core directly from ARM. These reference ARM CPUs are the ones you hear about that are named things like ‘Coretex A15‘ or ‘Cortex A57’.
- License the ARM instruction set and develop your own CPU from scratch.
Apple does the 2nd option, by the way. Yes, Apple is switching from Intel’s x86 platform to the much more efficient ARM instruction set.
This move is going to drive forward the desktop PC industry’s adoption of ARM hardware.
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