I'm not the most tech-saavy of people, so I apologize in advance.

I recently bought a an external hard drive, and have backed up all of my documents, music, and videos. However, I was wondering if there was software that would automatically back things up as they are added to my computer. For example, if I saved a file on my computer, it would automatically be backed up on my external hd.

Any help would be greatly appreciated! Again, sorry if this is a dumb question.
Its funny you should ask, my dad walked in my room not 2 min ago saying i should get Norton Ghost and run it once a week. It backs up everything to the other hard drive in my comp. I have two, and i back up each one to the other so im covered if either blows. There is nothing that automatically backs up stuff, if there was i can only imagine that your computer would run incredibly slow.
My laptop came with some NTI Backup Now software that has a schedule thingy but I dont use it. My Nero Suite also has a backup tool, so just pirate Nero 7 or something and install the Backup software only. I think Perfect Disk (Defragmenter) might do this too. Just pirate them and try em out.
I just found something on Download.com after about half an hour of searching, and it seems to be working well. Thanks for your help!