RISC OS

RISC OS is an <a href="/facts/Operating_system/8XTuvMh2">operating system</a> designed to run on <a href="/facts/ARM_architecture/SALsYA79">ARM</a> computers. Originally designed in 1987 by <a href="/facts/Acorn_Computers/jCddUElC">Acorn Computers</a> of England, it was made for use in its new line of ARM-based <a href="/facts/Acorn_Archimedes/BxInoqjT">Archimedes</a> personal computers and was then shipped with other computers produced by the company. Despite the demise of Acorn, RISC OS continues to be developed today by the <a href="/facts/RISC_OS_Open/FwaxGqAo">RISC OS Open</a> community on version 5.0 of the system that was <a href="/facts/Open_sourced/HzTaB8E9">open sourced</a> in 2018.
RISC OS is a <a href="/facts/Modular_programming/sNoqKvRD">modular</a> operating system and takes its name from the <a href="/facts/Reduced_instruction_set_computer/aQbGM62p">reduced instruction set computer</a> (RISC) architecture it supports. It incorporates a <a href="/facts/Graphical_user_interface/wBlQFWDP">graphical user interface</a> and a <a href="/facts/Windowing_system/nKYmkjP6">windowing system</a>. Between 1987 and 1998, RISC OS shipped with every ARM-based Acorn computer including the Archimedes line, Acorn's R line (with <a href="/facts/RISC_iX/bP9Ho0la">RISC iX</a> as a dual-boot option), <a href="/facts/RiscPC/82A6RIzn">RiscPC</a>, <a href="/facts/Acorn_A7000/9N8CFJXV">A7000</a>, and prototype models such as the Acorn <a href="/facts/Acorn_Computers/jCddUElC">NewsPad</a> and <a href="/facts/Phoebe_(computer)/XoJowynn">Phoebe computer</a>. A version of the OS, named <a href="/facts/NCOS/fA6RvPJt">NCOS</a>, was used in <a href="/facts/Oracle_Corporation/0z14FygH">Oracle</a>'s <a href="/facts/Network_Computer/6hHYFbN3">Network Computer</a> and compatible systems. 
After the break-up of Acorn, development of the OS was <a href="/facts/Fork_(software_development)/D6khxhpr">forked</a> and continued separately by several companies, including <a href="/facts/RISCOS_Ltd/SS6AmdSh">RISCOS Ltd</a>, <a href="/facts/Pace_Micro_Technology/NuGasPcu">Pace Micro Technology</a>, <a href="/facts/Castle_Technology/Kfgkkjb0">Castle Technology</a>, and RISC OS Developments. Since then, it has been bundled with several ARM-based desktop computers such as the <a href="/facts/Iyonix_PC/XJdlAzqe">Iyonix PC</a> and <a href="/facts/A9home/jYaCBEe2">A9home</a>. Most recent stable versions run on the ARMv3/ARMv4 <a href="/facts/RiscPC/82A6RIzn">RiscPC</a>, the ARMv5 <a href="/facts/Iyonix_PC/XJdlAzqe">Iyonix</a>, <a href="/facts/ARMv7/SALsYA79">ARMv7</a> <a href="/facts/Cortex-A8/vM6beXwg">Cortex-A8</a> processors and <a href="/facts/Cortex-A9/7frBGbbK">Cortex-A9</a> processors and the low-cost educational <a href="/facts/Raspberry_Pi/Ie6Lx9n5">Raspberry Pi</a> series of computers, with the exception of the Raspberry Pi 5.

RISC OS open-in-new

RISC OS