RAM is an abbreviation for Random Access Memory. This is a type of computer memory, that, in contrast to other storage devices such as hard disk drives or DVDs, enables the info to be accessed directly without reading the previous content located within it. Every time a program is started, it is stored inside the RAM, due to the fact that it can be accessed much more quickly than if it was read from another media. With regards to the hosting service itself, more RAM means that more web applications can operate concurrently on a certain server, particularly when they are resource-demanding and are accessed by a large amount of people simultaneously. Different from a shared web hosting solution where the system resources of a given account could be flexible and quite often depend on what other users consume as well, a VPS includes a guaranteed amount of RAM which you can use all the time. That memory is allocated to one server only and shall not be used by other customers even in case it's not being used.