An epitaph is an engraved message on a tombstone (the stone marker, not the frozen pizza). Generally, an epitaph would list the years of your birth and death, your name, and occasionally a message. In Fallout 2 you can see some humorous ones. "Here lies Ed Wood, one wood within another. The outer wood is very good, I can't vouch for the other."

The Epitaph is also the paper in Tombstone, Arizona.