What Does Virtual Memory (VM) Mean?
Virtual memory (VM) is a feature developed for the kernel of an operating system (OS) that simulates additional main memory such as RAM (random access memory) or disc storage. This technique involves the manipulation and management of memory by allowing the loading and execution of larger programs or multiple programs simultaneously. It also allows each program to operate as if it had infinite memory, and is often considered more cost effective than purchasing additional RAM.
Techopedia Explains Virtual Memory (VM)
In the 1940s and 1950s, prior to VM, large programs implemented logic to manage primary and secondary storage. The process was called overlaying. When a program was bigger than memory storage, the procedure allowed parts of the program that were not continuously used to be treated as an overlay. Each individual overlay would overwrite current overlay in memory. The programming for overlaying was extensive. One of the main reasons for creating VM was not for additional primary memory but for ease of programming. By 1969 the effectiveness of virtual memory was realized; and it became widely implemented.
