Expanded Memory Specification (EMS)

A technique, developed by Lotus/Intel/Microsoft (LIM), that adds addressable memory to a computer system, overcoming the original MS-DOS upper memory limit. The LIM EMS uses a 64-KB section of memory (usually in upper memory) to provide a "window" into which data can be written. Once in this area, the data can be transferred to the expanded memory. The memory chips are located on an expansion card installed inside the computer.