What is the gun formation?
Also know, why do they call it shotgun formation?
Shotgun Once the quarterback takes a few steps behind the line of scrimmage in anticipation of the snap, it is called the shotgun formation. The shotgun sprays the receivers all over the field. The origins date back to former 49ers coach Red Hickey and his need to beat the Baltimore Colts vaunted pass rush.
Also question is, what is the I formation in football?
The I formation is one of the most common offensive formations in American football. The I formation draws its name from the vertical (as viewed from the opposing endzone) alignment of quarterback, fullback, and running back, particularly when contrasted with the same players' alignments in the T formation.
It's just a nickname for the area between the 20 yard line and goal-line where an offense has a good chance at scoring. You could also say its a warning for opposing defenses to make a stop during the opposing team's drive. It's basically a nickname that came into being as a warning to the defense who is "in the red".