RAM, which refers to Random Access Memory, is a computer storage media which could be accessed faster than a disk drive, as the information can be read randomly, skipping the bytes before the needed info is reached. On a hosting server, the RAM is employed to load scripts and web programs after they are executed, so the more RAM you can use, the more applications you shall be able to run simultaneously and the more people will be able to look through your sites without effect on the site’s/server’s performance. In contrast to a disk drive, however, the RAM is used for temporary storage purposes, as the data is lost as soon as the power is shut off. When you use a shared web hosting account, the physical memory which your scripts could use may be limited and can change depending on what the other customers on the same machine use. With a virtual or a dedicated web server, however, you'll have a set amount of RAM that will not be used by others even if you don't use it at a particular time.