An offensive alignment that places the quarterback a few yards behind the center with a running back lined up behind him. The formation strives to give the quarterback the ability to analyze the defense by moving him back from behind center while still keeping him close enough to the line of scrimmage to make a quick play. Pistol formations tend to rely on a higher number of option plays and runs than other formations.
Think of the pistol formation as a combination of the traditional shotgun and single back formation offense.
The Pistol is becoming a more popular formation in the NFL because of it's ability to freeze defenses with a mix of downhill rush plays and wide-open passing from the same formation.
Also referred to as "Pistol Offense."
The pistol formation is a relatively new formation in professional football. By placing the quarterback much closer to the line of scrimmage than the more traditional shotgun formation, the quarterback is able to initiate the play in a better location, but he still benefits from being able to see over the offensive line before the snap.
The other main difference in the pistol formation is that the running back is still lined up directly behind the quarterback. This allows for a variety of run and option plays out of the formation that are unavailable in the shotgun. Most quarterbacks that are effective in the pistol formation are "dual-threat" quarterbacks: athletic players that can both run and throw on any given play.