Life...By the Book - Communion

What does the Bible say about communion? How much do we really understand about the Lord's Supper? When and where did Jesus institute this memorial? What is the significance of its roots in the Passover? Why are the elements - the bread and the cup - unleavened, or unfermented? How often should we partake together? What should be the manner of our observance? What are the four "looks" Paul mentions in 1 Corinthians 11 that should always be a part of how we eat/drink when we come to the Lord's Table?