'Confused' from California

Joined the forum to learn more about SEO. I'm particularly interested to know how my website got a Google page rank 4 two months after I launched it. One forum member here said that PR is based on the total backlinks a page is getting. Well, guess what... there are only 5 sites linking to my website. I'm confused.

Are you Confused?

Where abouts in Cali are you from?
Nor cal...here