Linebackers: they are the "clerics". If a sentence like this makes everything about NFL football a lot clearer to you, this is a MUST READ.

My favorite part of this article:

Football has been in open beta for 144 years. The original goal of the developers was to create a game that roped together more than five centuries of rugby history into a more spectator-friendly, strategically deeper game.

Rugby is a fascinating game, if considerably less polished than American Football. Rugby is a sport that the very idea of folklore itself designed. As such, it's not good for newcomers to the sports strategy genre. Give it time. You'll soon find it's easily one of the top three best ways to legally hurt other people.

Where Football excels over its spiritual predecessors is the implementation of the "system of downs" feature—which we touched on briefly above. Breaking up a "drive" toward a "touchdown" into four-part mini-battles, adding chances for continues and resets to "first down" for highly successful plays really helps funnel the juice of the strategy into a meatier game.

Football goes one magnitude deeper by implementing elements of a turn-based rugbylike with "the huddle": between downs, the coach relays play formations to the quarterback, who then takes the play to the rest of the team. In a secret on-field meeting called a "huddle," the quarterback communicates the play to the rest of the team. They have forty seconds to decide their play, line up, and prepare for "the snap." (Taking longer than forty seconds earns a "delay of game" penalty.)

One player on the offense, known as the "center," is in control of the start of the play. When he shouts "set," all players on the field must stand still for one second. When one second—or more, if the offense wants to hammer in suspense—has passed, the center "snaps" the ball to the player behind him. Now the game is officially being played: the center class-changes in an instant, and is now a blocker.

The game has switched from turn-based mode to real-time mode in a heartbeat.

In real-time mode—while the game is in play—it all comes down to whether or not the players on the field can live up to the coaches' expectations, and perform their heroic physical duties under intense pressure. This is where the first layer of psychological randomness falls into place.

After the snap, the quarterback—or "QB"—has the ball. He can hand it to one of his runningbacks, or he can pass it to a wide receiver. Or he can run it himself.

Almost every play formation gives the quarterback options, because the heavy tome of Footballplay formation history has taught coaches and players that sometimes, anything can happen.

The QB has to think quickly: ahead of him the center, two guards, and two tackles—the biggest, toughest players on the offensive team—are pushing back with all their might against the defensive linemen—the biggest, toughest players on the defensive team. Whose "tanks" are tougher than whose? That's a question that a game of Football asks dozens of times in its course, and the answer is never always the same.