I've decided on a new feature here at Dave's: a primer to football, with focus on the Dolphins. I figure I'm a student of the game, and its time to impart some of my knowledge to fans who are learning the sport and want to know more.
Ready? Here goes.
Let's start off with the basics. And I mean the real basics. On any given play, its 11 on 11. Even on special teams (kickoffs, punts, and field goals). From How Stuff Works , here's a diagram of how the players lineup on offense and defense:
There always must be 7 players on the line of scrimmage (draw a line from sideline to sideline where the football is placed). The other 4 can be lined up anywhere: on the line or behind it. No one can be lined up beyond it. But, there are a few catches. The ball must be hiked (passed from between the legs) from someone (the center because he's at the center of the line) to someone else (and this does NOT have to be the quarterback). So, realistically, there has to be one guy in the backfield. Also, there are kind of specific rules about who can go out for a pass and be "eligible" to receive it. We'll get into the specific nuances of that rule in a future discussion. For now, lets generalize and say that along the line, only the guys at the ends can be eligible. Since they are far away from the center and can receive, they are called "wide receivers" (catchy, no?)
Note that in the picture, the wide receiver on the right is actually shown behind the line; that makes the tight end eligible as well.
Guys in the backfield are also eligible to catch a pass. Their names are typically half back, and full back. Here's how the names are derived:
quarter of the way back
half of the way back
all the way (or full) back
Although they don't always line up this way, that's how their names came about.
Before the snap, everyone must set. Lineman have to stop moving, and all but one other guy has to stop too. The offense can put any of the receiver in motion - that is moving in any direction except turning "up the field" like he's going out for a pass.
We'll get into how the players move and what happens later. For now, that sets the lineup.
Defenses can play any formation they like. Typically, coaches rely on a set of three defensive linemen, four linebackers (they back up the line), and four defensive backs (because they play back away from the ball), referred to as a 3-4, or have four defensive linemen, three linebackers, and four defensive backs, reffered to as a 4-3. They can vary that, of course, but those are the two most basic formations. Why pick one over another? It dependes on whether you want to control the line with more players matched up against the offensive line, or whether you want to have more guys running around free to make tackles.
The play on defense can get fairly sophisticated. But, the general nature is that the defensive lineman occupy the offensive line. The linebackers make sure that the tight end and running backs are accounted for, two of the defensive backs cover the receivers on the corners of the field (these are called "corner backs") while the other two prevent a big play that might happen if someone gets free. They're called safeties, because they provide a safety net on the field. A last line of defense.
In another session, we'll get into what the defense does, and how the plays break down.
But, for now, this should give you an idea of who's out there, and what they do.
Your homework is to memorize the names of all the positions. There will be a test on it the next time we meet.
Class is dismissed.