RAM is an abbreviation for Random Access Memory. This is a type of computer memory, which, in contrast to other storage devices such as harddrives or DVDs, enables the info to be accessed directly without reading the previous content stored in it. Whenever an application is started, it is stored inside the RAM, since it may be accessed much more quickly than if it was read from another media device. In terms of the hosting service itself, more RAM means that more web apps can operate all at once on a particular server, especially if they're resource-demanding and are accessed by a large amount of people at the same time. Unlike a shared web hosting package in which the system resources of a particular account can be flexible and sometimes depend on what other users consume also, a VPS provides a guaranteed amount of RAM which can be used all the time. That memory is allotted to one web server only and shall not be used by other customers even if it is not used.