What it is

The 53-man roster is the group of players an NFL team can have on its active list during the season. Not all are in uniform for a game.

In a game

On game day, only part of the roster is active, so the rest are inactive. Players on the practice squad can be signed to the roster when needed.

More detail

The roster must be cut down from a larger number before the season begins. Teams use the rest of the roster spots for backups, specialists and injured players.