The Computer Revolution/Hardware/Virtual Memory

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Virtual memory is not virtual at all, it is a part of the hard disk that is used to perform some of the functions of RAM if more memory is required to run things than the RAM can provide without slowing down. Virtual memory then is simply a portion of the hard disk which has been appropriated for RAM activities. Virtual memory is a common part of most operating systems found in desktop computers. Because the ram on the ordinary computer isn’t enough to run all of the programs that most users need to at the same time, virtual memory is required. Without virtual memory you would not be able to open a web browser and a word processor program at the same time. Virtual memory allows the computer to look at RAM for areas that have not been used recently and copy them onto the hard disk. This frees up enough space in RAM so that the user can load the new program. Since the hard disk space is much cheaper than RAM chips, virtual memory has an economic benefit to it. However, since the read/write speed of a hard drive is much slower than RAM the user may find that there is a performance drop if the computer relies too heavily on the virtual memory. The key for the user is to have enough RAM to handle everything they tend to work on simultaneously so that the only time there seems to be slowness due to virtual memory reliance is when they’re changing tasks only.