An audible.
QB (quarterback) instructs his teammates to listen carefully at the line of scrimmage because he may call another play, or his call at the line of scrimmage will be the play.
it is not legal to drop kick beyond the line of scrimmage. all you can do beyond the line of scrimmage is pitch the ball backwards.
When they are five yards behind the line of scrimmage they call that the SHOTGUN formation.
there must be 7 men on the line of scrimmage, no more no less
Line of scrimmage.
on tv, the line of scrimmage is usually blue and the first down line is usually yellow.
the line of scrimmage
The line of scrimmage.
On the offensive side, nobody has to be in a down position on the line of scrimmage, but there must be six men on the line. The defense does not have any regulations as to where they must line up on the line of scrimmage.
In the NFL, there is no such thing as pass interference (PI) on forward passes that do not go past the line scrimmage but I recently watched a college football game in which a PI was called on a forward that never reached the line of scrimmage even though I always believed that there is no such thing as PI if such pass was in the backfield (behind the line of scrimmage). So I am not clear on the rule concerning passes that do not cross the line of scrimmage, in college football.
The offense is allowed up to ten players on the line of scrimmage, need one to receive the ball from the center. But the offensive is required to have a minimum of seven players on the line of scrimmage. Defensively all eleven can play on the line of scrimmage.