I'll just go ahead and have a shot at explaining what RAM is as well.
Ok, so imagine that you're writing an essay, but you have a limited volcabulary. So you get a dictionary (this being the computer harddrive) and start writing the essay using this. But you quickly realize that you keep looking up the same words again and again, so you devise a new solution: Writing down your commonly used words in a quickly-accessable notebook (this being the comptuer RAM).
But wait... suddenly your notebook starts to fill up, so you decide to put some sheets of paper from the notebook
back into the dictionary (let's just say underneath the front cover). This was supposed to illustrate what the harddrive's
page file does... It's simply a slow backup solution for the RAM. So if you're browsing the net in Internet Explorer and then open a game, the game will need so much RAM that Windows will have to free up some RAM by swapping Internet Explorer into the pagefile.
Comprendes?