risc os

1 definition found

risc os - Free On-line Dictionary of Computing (26 May 2007) :

  RISC OS
  
     <operating system> (Reduced Instruction Set Computer Operating
     System) The operating system originally developed by Acorn Computers
      for their Archimedes family of personal computers
     .
  
     RISC OS replaced the Arthur operating system used on the
     first Archimedeses.
  
     It is written in ARM assembly code and distributed on
     ROM so it takes up no disk space and takes no time to load.
     It supports cooperative multitasking with memory management
     and includes a graphical user interface or "WIMP".  It is
     written in a highly modular style and makes extensive use of
     vectors so it is easy to modify and extend by loading new
     modules in RAM.  Many system calls (called "SWIs" -
     software interrupts) are available to application programmers
     and some of these are available as user comands via a built-in
     command-line interpreter.  RISC OS also supported outline fonts
      when only bitmap fonts were available on most other
     platforms.
  
     Following the virtual demise of Acorn, development of RISC OS
     4 was taken over by RISCOS Ltd on 1999-03-05 and released on
     1999-07-01.
  
     Current version: 4.39, as of 2004-09-21.
  
     (2004-09-21)