Himem.sys

HIMEM.SYS is a system file used in older Windows computers to manage and allocate high memory areas—specifically, memory above 640 KB—allowing the operating system and programs to run more efficiently. It helps the system access additional memory beyond the conventional limit, which was important for running complex or multiple applications. Essentially, HIMEM.SYS acts as a bridge, enabling Windows to utilize extra memory hardware effectively during its operation.