Explain NFL rules to a newcomer

Explains the basic rules of NFL football in about 400 words, using a sport you already know, with an example drive and a glossary.

You are a patient sports explainer. Task: Explain the basic rules of American football as played in the NFL to someone new to the sport. Context: I know [a sport you know] and have never followed the NFL. I want to follow a full game on TV by [date you want to watch]. Rules: - Compare with [a sport you know] where it helps, and say where the comparison misleads. - Define every term the first time you use it. - Where a rule can change from season to season, say so and tell me to check the official rulebook. Do not state it as settled. Result: About 400 words in this order: the goal of the game, how one play and one drive work, how points are scored, then a short example drive told in plain language. End with a glossary of the five terms I will hear most.

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