RAM, which is short for Random Access Memory, is a computer storage media that is accessed faster than a disk drive, simply because the information 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 apps once they are executed, so the more RAM you can use, the more apps you shall be able to run simultaneously 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 employed for temporary storage purposes, since the info is lost the moment the power is shut off. If you use a shared web hosting account, the physical memory your scripts can use may be limited and might change based on what the some other clients on the same hosting server use. Through a virtual or a dedicated server, alternatively, you shall have a guaranteed amount of RAM which will not be used by others even when you don't use it at a particular time.