Look to the steeple of any Catholic church.  See that!  It’s a cross, symbol for Jesus Christ, man of God who lived a long time ago and died by execution on a cross.  He greatly impacted the people of his society and by means of his recorded teachings has had a continuing influence on human culture.  For example, he preached, "do unto others as you want others to treat you."  Also, "the kingdom of God is in your midst."  The cross was made by fastening two tree limbs or wooden beams together at their centers, crosswise, so that the shorter beam formed a horizontal axis (in relation to the ground) and the longer a vertical line.  A person could be attached to this structure and made to hang thereon until dead.  Jesus was nailed to a cross.  This mode of execution provided a spectacle for onlookers (showing the power of the government) and extended suffering for the criminal.  Governments no longer use crosses to kill criminals, but the cross, as symbol of Jesus Christ, is ubiquitous on planet Earth.