RAM is an abbreviation for Random Access Memory. This is a sort of computer memory, that, unlike other storage devices like hard disk drives or DVDs, enables the data to be accessed directly without reading the previous content located in it. Each time an app is launched, it is stored in the RAM, due to the fact that it could be accessed much more quickly than if it was read from another media device. With regards to the hosting service itself, additional RAM means that more web applications can work simultaneously on a certain hosting server, especially if they're resource-demanding and are accessed by a large amount of people simultaneously. Unlike a shared web hosting package in which the resources of a certain account could be flexible and frequently depend on what other end users consume also, a VPS offers a guaranteed amount of RAM that can be used always. That memory is assigned to one hosting server only and will not be used by other clients even if it is not in use.