RAM, that is short for Random Access Memory, is a computer storage media that may be accessed much faster than a disk drive, because the info can be read randomly, skipping the bytes before the needed data is reached. On a server, the RAM is employed to load scripts and web applications once they are executed, so the more RAM you can use, the more apps you will be able to run all at once and the more people will be able to check out your sites with no effect on the site’s/server’s functionality. Unlike a disk drive, however, the RAM is used for non permanent storage purposes, as the info is lost as soon as the power is shut off. When you use a shared web hosting account, the physical memory which your scripts are able to use may be limited and could change based upon what the other customers on the same machine use. With a virtual or a dedicated web server, on the other hand, you'll have a guaranteed amount of RAM which won't be used by others even if you do not use it at a particular time.