Concept Of Virtual Memory. This technique virtualizes a computer architecture's various hardware memory devices (such as ram modules and disk storage drives), allowing a program to be designed as though: Virtual memory is used to give programmers the illusion that they have a very large memory even though the computer has a small main memory.

In computing, virtual memory, or virtual storage is a memory management technique that provides an idealized abstraction of the storage resources that are actually available on a given machine which creates the illusion to users of a very large (main) memory. Here, we take windows xp for example to show how to set the virtual memory. It is very helpful in implementing a multiprogramming environment.