ARM is the name of a popular CPU architecture. It is used on most portable devices today.
ARM was developed back in the '80s' by Acorn systems as a RISC (reduced instruction set computer) to provide a low power substitute for the larger and more power hungry devices from companies like Intel that used a much larger instruction set and therefore more complex chips which came to be known as CISC, Complex Instruction Set Computers (See X86). The name ARM is an acronym for Acorn RISC Machines. It was changed to Advanced RISC Machines when ARM was spun off from Acorn.
Today the ARM computers are the most popular 32 bit architecture that is in use in the world. The architecture is used on most cell phones and other portable devices including eBook readers except those made by recently by Apple which developed its own variant RISC processors, although its earlier devices used ARM. New Apple hardware beginning with the A7 is 64 bit based using ARM compatible architecture. Newer Android 5.0 devices also use 64 bit ARM based processors. Qualcomm's latest and greatest processors are also 64bit, for example the Snapdragon 835.
 ARM processors in the wiki
- Nvidia Tegra
- Samsung makes processors for many of the devices in this wiki.
- Freescale features built-in EPD controller on some models.
 OS for ARM
Most of the standard Operating Systems have a variant for ARM processors. Some only work in this hardware. These include:
- iOS - For Apple based hardware.
- My RISC OS
- PalmOS PDAs
- RISC OS Open - derived from the first ARM OS.
- Symbian OS
- Windows 8 RT
- Windows Mobile
- Windows phone