According to their website:
I say that it is like a virtual scrapbook where you take images and products off the Internet or from those whose pictures are already posted and pin it to your boards. Boards are pins that are named by catagories that Pinterest has or you can create your own. Some of mine are Child of God, Coffee, Back in My Time, Places I Love, Facinating Jewelry, Mother Nature, and Straight/Christian for Gay Rights. You can follow what specific people put on all of their board or select board that interest you.