Disclaimer: this might be a little technical. Hang in there. Let's talk about Google PageRank. PageRank discussion can become technical and detailed (if you want to learn more about). However, you don't need to get too technical, but you should know the basics. If you want to walk away with one take away, here it is:
PageRank is a popularity score (0-10), calculated by Google by counting links from other sites, which determines how high your page can rank for certain keywords. The higher, the better. It's like a voting system, more and higher quality links your attracts, better it will do on the Search Engines.
That's it. If you want to learn more about PageRank, review the infographic created by ZippyCart. It explains the concept in easier terms. Otherwise, that's all you need to know about PageRank.