RAM, that stands for Random Access Memory, is a computer storage media which can be accessed much faster than a hard drive, due to the fact that the information can be read randomly, skipping the bytes before the needed information is reached. On a hosting server, the RAM is used to load scripts and web programs after they are executed, so the more RAM you may use, the more applications you'll be able to run simultaneously and the more people will be able to check out your Internet sites with no effect on the site’s/server’s overall performance. Different from a disk drive, however, the RAM is used for temporary storage purposes, since the information is lost as soon as the power is shut off. When you use a shared web hosting account, the physical memory which your scripts can use may be limited and might change depending on what the other customers on the same machine use. Using a virtual or a dedicated web server, alternatively, you will have a fixed amount of RAM that will not be used by anyone else even if you don't use it at a certain time.