riscos

RISC OS is a family of operating systems for ARM-based computers, originally developed by Acorn Computers in the 1980s for the Archimedes line. It was initially released under the name Arthur and later renamed RISC OS as Acorn shifted its focus to ARM hardware.

The system is known for its graphical user interface built on a Windows, Icons, Menus and Pointer (WIMP) paradigm. It uses a modular toolkit architecture, with the Toolbox providing GUI components and a consistent application interface. The desktop environment emphasizes a compact footprint, fast startup, and built-in support for multiple programming languages, including BBC BASIC. The file system and application model are designed to be portable, helping software portability between compatible ARM machines.

Beyond Acorn’s demise, the RISC OS project continued in two main strands: RISCOS Ltd and, later, RISC Open Limited (ROOL). Open-source components were released under ROOL’s licenses, and modern editions are distributed as RISC OS 5 and its successors. Community ports have extended the OS to a range of ARM boards, notably the Raspberry Pi, and to emulators such as RPCEmu.

Today, RISC OS remains active in education, hobbyist, and preservation communities. It is valued for its performance on modest hardware, lightweight footprint, and scriptable environment, with ongoing development by dedicated volunteers and companies.