What's the difference between the NFL rulebook and the U.S. tax code? One is about sports. And, well, that's about it.

The NFL's playing rules break down into sections, articles, items, exceptions, examples and other subsets. Many rules apply only during specific time periods of a game. Some depend on the position of the player, and others are dependent on the position of the player on the field. (Understand the difference?)

Even veteran officials have gotten confused and misapplied rules this season. See if you can do better. Take our quiz to find out!