RAM is an abbreviation for Random Access Memory. This is a type of computer memory, which, different from other storage devices like hard disk drives or DVDs, permits the information to be accessed directly without reading the previous content located in it. Every time an app is started, it is stored inside the RAM, due to the fact that it can be accessed much faster than if it was read from another media. With regard to the web hosting service itself, more RAM means that more web apps can operate concurrently on a given hosting server, especially when they are resource-demanding and are accessed by a great number of of people all at once. Not like a shared web hosting package in which the system resources of a particular account may be flexible and often depend on what other users consume also, a VPS provides a guaranteed amount of RAM that can be used at all times. That memory is allotted to one hosting server only and will not be used by other clients even if it is not being used.