Modes of Multitasking

In the early days of the PC, some people advocated multitasking for the future, but many others scratched their heads in puzzlement: Of what use is multitasking on a single-user personal computer? Well, it turned out that multitasking was something users wanted without really knowing it.

Multitasking Under DOS?

The Intel 8088 microprocessor used in the original PC was not exactly built for multitasking. Part of the problem was inadequate memory management. As multiple programs are started up and ended, a multitasking operating system is often called upon to move memory blocks around to consolidate free space. This was not possible on the 8088 in a manner transparent to applications.

DOS itself didn’t help much. Designed to be ...

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