Could someone give me the basics?

Hi everyone, I want to learn SEO. Not only for my own sites but maybe to offer my services to others.

So far, I think I know about backlinks but that is it. The higher the page rank of the site, the more value your backlink has, but you can also get Xrumer and get a lot of bad backlinks to balance out the quantity and quality.

What I don't understand is pretty much everything but that. Keywords, Directory submissions, etc.

Could anyone explain the basics (BH or WH) or direct me somewhere that can?

Thanks,

Jared