A Latin cross or Crux immissa is a type of cross in which the vertical beam sticks above the crossbeam. This is the main representation of the cross by which Jesus Christ was crucified. The Latin cross began as a Roman Catholic emblem but later became a universal symbol of Christianity. If displayed upside down it is called St. Peter's Cross because he was reputedly executed on this type of cross. When displayed sideways it is called St. Philip's cross for the same reason.