RAM, that is short for Random Access Memory, is a computer storage media which is accessed considerably faster than a hard disk drive, simply because the info can be read randomly, skipping the bytes before the needed information is reached. On a hosting server, the RAM is employed to load scripts and web applications when they are executed, so the more RAM you are able to use, the more applications you will be able to run all at once and the more people will be able to browse your sites with no effect on the site’s/server’s functionality. Unlike a disk drive, however, the RAM is employed for temporary storage purposes, as the information is lost once the power is shut off. If you use a shared web hosting account, the physical memory that your scripts can use may be limited and might change based upon what the other customers on the same hosting server use. Using a virtual or a dedicated hosting server, however, you'll have a set amount of RAM that won't be used by anybody else even if you do not use it at a certain time.