The name given to memory in an Intel PC above 1MB. Starting with the Intel 286, it was used directly by Windows and OS/2 as well as DOS applications that ran with DOS extenders. It was also used under DOS for RAM disks and disk caches. Contrast with expanded memory (EMS), which was specialized memory above 1MB. Today, the term is rarely heard, because the 1MB barrier was broken long ago. See EMS, XMS and DOS extender.
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