What are all the officials on a football field?

Answer 1

The Ref is the head official and has final say on rulings. The Umpire stands behind the defense, watching the defensive line for illegal holds or other infractions. The Head Linesman stands to one end of the line of scrimmage, watching for possible offsides or other "neutral zone" infractions. The Line Judge stands on the other end of the line of scrimmage, and assists the Head Linesman with watching for offsides or other "neutral zone" infractions. The Field Judge stands downfield behind the defensive secondary, along the same side as the Line Judge. He watches for pass interference, illegal blocks, and incomplete passes. He sometimes serves as backup timekeeper, and also rules on field goals along with the Side Judge. Side Judge is the same as the Field Judge, but works the other side of the field, and is responsible for the game clock and play clock. The Back Judge stands behind the defense and is responsible for delay of game penalties and also illegal holds, blocks, or other penalties, and is the official timekeeper.