Programming Windows®, Fifth Edition

Chapter 20. Multitasking and Multithreading

Multitasking is the ability of an operating system to run multiple programs concurrently. Basically, the operating system uses a hardware clock to allocate “time slices” for each currently running process. If the time slices are small enough—and the machine is not overloaded with too many programs trying to do something—it appears to a user as if all the programs are running simultaneously.

Multitasking is nothing new. On large mainframe computers, multitasking is a given. These mainframes often have hundreds of terminals attached to them, and each terminal user should get the impression that he or she has exclusive access to the whole machine. In addition, mainframe operating systems often allow users ...