RAM is an abbreviation for Random Access Memory. This is a type of computer memory, which, unlike other storage devices such as hard disk drives or DVDs, enables the information to be accessed directly without reading the previous content stored inside it. Anytime an application is launched, it's stored in the RAM, because it could be accessed considerably quicker than if it was read from another media. With regard to the hosting service itself, extra RAM means that more web applications can operate all at once on a particular server, especially if they're resource-demanding and are accessed by a large number of people all at once. Unlike a shared web hosting plan in which the resources of a certain account may be flexible and sometimes depend on what other users consume too, a VPS features a guaranteed amount of RAM that can be used always. That memory is allotted to one web server only and shall not be used by other clients even when it is not used.