Operating systems

All PC functions are controlled by an operating system (OS); applications are written to run under a specific OS; it is therefore important to know what is necessary to run a specific PC and a specific application:

· the DOS (Disk Operating System) is the oldest OS; it works on small equipment; its different versions followed the market trends and technological improvements (e.g. bigger memory management, etc.).

· WINDOWS is not really an OS in itself; it is a powerful graphic interface for DOS users, which makes their work much more friendly. It helps to manage extended memory; to integrate various applications, exchanging files via its clipboard. Different versions exist, as well as multimedia extensions;

· OS/2 is a multitasking and multiusers IBM OS which means that the user can execute different programs simultaneously (e.g. printing a file while working on another one, or formatting a diskette while updating a data base or a spreadsheet). It allows DOS and WINDOWS applications to be run under its control; different versions are available, as well as multimedia extensions;

· APPLE System 7 runs on the Apple series of computers;

· UNIX is a multiusers, multitasking operating system, mainly used on workstations. More powerful than usual PCs; multimedia capabilities have been added to the software.²²

²² Multimedia premies on UBIX workstations - David SIMPSON - Systems Integration -January 1992.