Win32 System Services: The Heart of Windows® 98 and Windows® 2000

6.2. Introduction

If you are moving to Windows 2000 from UNIX, VMS, or a mainframe, then multi-processing is a concept familiar to you. Multi-threading, however, may be new to you. If you are moving from MS-DOS, then both multi-processing and multi-threading are probably new to you. Let's start by looking at what multi-processing and multi-threading actually mean from an operating-system standpoint.

The MS-DOS operating system is a single-tasking operating system. It can run one program at a time. You load a program, work with it, quit it, and then run another. TSRs can, in certain situations, give an impression of multi-processing. However, the problems that TSRs normally cause show that they are, at best, an illusion that MS-DOS was never ...