Oh good! Finally, the clear and friendly explanation of PGN that you have all been waiting for! The only thing is, I can't take any credit for it! Ha! When Emily posted her explanation of PGN, I knew she had it pegged, so I asked her if I could bring you all along to her site to check it out... she welcomes you. While you are there learning the details of PGN, take a little time to introduce yourself to her sweet baby, Nathaniel.
Hope this helps. FYI- We are with the "first reviewer".
PGN EXPLANATION BY EMILY