REMEMBER: You may think running backs only run with the ball. But, a running back can also catch passes as a receiver.
On a passing play the receiver looks to get open on the field for a pass thrown by the quarterback. A completion is a pass that's caught. An incompletion is a pass that is not caught or a throw that goes out of bounds.
A wide receiver is a receiver who stands wide near the sidelines at the start of a down on the scrimmage line. Wide receivers run complex routes on the field to fool defensive players and to create openings on the field to catch passes.
A tight end is a receiver that is more flexible than a wide receiver. Tight ends can be extra blockers or catch passes based on the play design. Tight ends are on the strong side of the football field.
LINGO ALERT: The strong side of the field is the side that the tight end is on. The weak side is the other side of the field. The strong side is used in play designs.