)(n.) An imaginary memory area supported by some operating systems (for example, Windows but not DOS) in conjunction with the hardware. You can think of virtual memory as an alternate set of memory addresses. Programs use these virtual addresses rather than real addresses to store instructions and data. When the program is actually executed, the virtual addresses are convertedinto real memory addresses.
The purpose of virtual memory is to enlarge the address space, the set of addresses a program can utilize. For example, virtual memory might contain twice as many addresses as main memory. A program using all of virtual memory, therefore, would not be able to fit in main memory all at once. Nevertheless, the computer could execute such a program by copyinginto main memory those portions of the program needed at any given point during execution.
To facilitate copying virtual memory into real memory, the operating system divides virtual memory into pages, each of which contains a fixed number of addresses. Each page is stored on a diskuntil it is needed. When the page is needed, the operating system copies it from disk to main memory, translating the virtual addresses into real addresses.
- Watch Datamation's editor James Maguire moderate roundtable discussions with tech experts from companies such as Accenture, Dell, Blue Jeans Network, Microsoft and more »
It's not just your lawnmower and household tools that your neighbor won't return. Our top picks include everything from updating device firmware... Read More »Interesting Times: Transformation in the IT Channel
Business transformation will remain the buzzword of the moment as channel firms continue to assess the direction of their companies in the age of... Read More »What is a Virtual Private network (VPN)?
Companies and organizations will use a VPN to communicate confidentially over a public network and to send voice, video or data. Read More »
From wacky alarm clocks to lecture hall tools and after class entertainment, these Android apps are a good fit for a student's life and budget. Read More »Network Fundamentals Study Guide
A network is a group of two or more computer systems or devices, linked together to share resources, exchange files and electronic communications.... Read More »Computer Architecture Study Guide
This Webopedia study guide describes the different parts of a computer system and their relations. Read More »