Two offences can use exactly the same personnel and look completely different before the snap. That is because personnel and formation are not the same thing.
Personnel first, formation second
Take 11 personnel: one running back, one tight end and three wide receivers. Those same five skill players can line up in shotgun spread, a bunch set, a condensed formation or with the tight end detached from the line.
Why alignment matters
Alignment changes leverage. A receiver split wide creates more horizontal space inside. A condensed receiver alignment can create easier crossing routes and better blocking angles. A tight end attached to the line can make a defence treat that side as the stronger run surface.
Eligible receivers
Only certain offensive players are eligible to catch a forward pass on a normal play. The five offensive linemen are normally ineligible; the remaining skill players can be eligible if they are aligned legally.
That is why commentators talk about a player being “covered up” on the line. Formation rules determine who may release into a route.
Common formation words
| Term | Simple meaning |
|---|---|
| Shotgun | Quarterback several yards behind the centre. |
| Under centre | Quarterback directly behind the centre for the snap. |
| Trips | Three eligible receivers aligned to one side. |
| Bunch | Three receivers aligned tightly together. |
| Empty | No running back in the backfield beside or behind the quarterback. |
| Condensed | Receivers aligned closer to the formation than a normal wide split. |
Viewing tip: personnel tells you the pieces. Formation tells you how the offence is arranging those pieces to create leverage.