RAM is an abbreviation for Random Access Memory. This is a type of computer memory, that, different from other storage devices like hard disks or DVDs, allows the info to be accessed directly without reading the previous content saved in it. Each time an app is started, it's stored within the RAM, since it can be accessed considerably quicker than if it was read from another media. In terms of the hosting service itself, additional RAM means that more web applications can operate all at once on a certain web server, particularly if they're resource-demanding and are accessed by a significant number of people simultaneously. Not like a shared web hosting package in which the system resources of a particular account can be flexible and sometimes depend on what other end users consume too, a VPS features a guaranteed amount of RAM which can be used at all times. That memory is allocated to one web server only and will not be used by other customers even when it is not being used.