ABSTRACT
An operating system is the set of programs that control a computer. Some operating systems you may have heard
of are Unix (including SCO Unix, Linux, Solaris, Irix, NetBSD, and FreeBSD), the Microsoft family (MS-DOS,
MS-Windows, Windows/NT, Windows 2000, Windows 2003, Windows XP), IBM operating systems (MVS, VM,
CP, OS/2), Macintosh operating systems (Mac OS), Mach, and VMS. Some of these (Mach and Unix) have been
implemented on a wide variety of computers, but most are specific to one or two particular architectures, such as
the Digital Equipment Corporation Vax (VMS), the Intel 8086 and successors (the Microsoft family, OS/2), the
Motorola 68000 and successors (Mac OS), and the IBM 360 and successors (MVS, VM, CP).
