Refers to a variety of methods used to store data and programs in memory, keep track of them and reclaim the memory space when they are no longer needed. It also includes virtual memory, bank switching and memory protection techniques.
It Used to Be a Nightmare
In the days of the first PCs, memory management used to be a major consideration. The PC had more confusing memory types than any computer in history as its architecture was pushed, patched and expanded to meet the increasing demand for more capabilities. DOS, the operating system of the 1980s, was designed to address only one megabyte (1MB) of memory. Today, we take 512MB and 1GB for granted, and Windows uses up every available drop.
In the first decade of the PC, technicians had to deal with conventional memory, upper memory, high memory, extended memory and expanded memory in order to support growing applications. Countless books were written on PC memory management. There were even three-day courses on the subject. Eventually, subsequent versions of DOS, and especially Windows, added the necessary memory management functions to eliminate the manual, time-consuming tweaking and configuring how much memory should be reserved for this and how much for that. See memory allocation, virtual memory, garbage collection, memory protection, EMS, EMM and DOS memory manager.
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