RAM, which means Random Access Memory, is a computer storage media that could be accessed noticeably faster than a hard drive, due to the fact that the information can be read randomly, skipping the bytes before the needed data is reached. On a web server, the RAM is employed to load scripts and web apps once they are executed, so the more RAM you may use, the more apps you will 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 performance. Unlike a disk drive, however, the RAM is used for non permanent storage purposes, because the data is lost as soon as the power is shut off. If you use a shared web hosting account, the physical memory your scripts can use may be limited and could change depending on what the some other clients on the same machine use. Using a virtual or a dedicated hosting server, alternatively, you shall have a set amount of RAM which will not be used by others even when you don't use it at a certain time.