RAM, which means Random Access Memory, is a computer storage media that is accessed considerably faster than a hard drive, because the data can be read randomly, skipping the bytes before the needed info is reached. On a web server, the RAM is employed to load scripts and web programs when they are executed, so the more RAM you can use, the more programs you will be able to run concurrently and the more people will be able to explore your sites without effect on the site’s/server’s functionality. Different from a disk drive, however, the RAM is used for momentary storage purposes, because the information is lost when the power is shut off. In case you use a shared web hosting account, the physical memory which your scripts could use may be limited and may change according to what the other customers on the same web server use. Through a virtual or a dedicated hosting server, however, you shall have a fixed amount of RAM that won't be used by others even if you don't use it at a given time.