You’re correct, but I was trying to not get the OP dragged down in too many details. 
Oh, and if you’re watching the game, and want to know when to cheer: For the offense, a good play is one where you make a first down, and a great play is one where you make a first down and then get a bunch of yards beyond that (ideally, ending with a score). A play where you get positive advancement but don’t make the first down might or might not be decent, depending on how many yards, and what down it is. For instance, advancing four yards on first down is decent (do that a couple more times and you’re good), but if it’s 3rd and 15, then advancing ten yards doesn’t do much.
For the defense, any play where you prevent a positive gain is a good one (most often, an incomplete pass), better if you can make them take a loss. A great play is one that leads to a significant loss of yardage, or a turnover. The absolute best play would be a turnover followed by a long run into a touchdown, like the Steelers did to the Cardinals at the end of the first half of Super Bowl 43.
To nitpick, that’s for defensive pass interference, the more usual kind. Offensive pass interference is a 10 yard penalty from the previous spot. And to further nitpick both are for NFL rules. College ball has slightly different penalties for interference (for example, college ball has a max of 15 yards for offensive pass interference, which actually incentivizes just aggressively interfering on a long bomb that has a decent shot of being caught.)
ETA: Of course, for the very basics of the game, this is probably not important, but it’s still fairly early-level knowledge, since pass interference is an important and fairly common penalty in football.
The best, most coherent explanation of American football was provided by Andy Griffith.
Um, that should read “defensive pass interference” not “offensive pass interference” there. :smack:
One of the useful watching tips it took me a while to learn …
When the two sides line up, there are five beefy guys along the front of the offense. They’re the “Offensive Line”. On a typical running play, they will burst forward and try to create gaps. On a typical passing play, they will fall back to create a protected “pocket” for the quarterback.
It’s easiest to tell what is going on if you watch what the offensive line are doing first, rather than trying to work out what is happening by watching the quarterback. The quarterback is trying to deliberately mislead using his body language, so it’s easy for your eyes to get sucked in the wrong direction.
If the offensive line falls back, it’s a contest for the defense to get to the quarterback before the quarterback gets the ball to an open receiver. There will be a main person they are trying to throw two, and one or more backup options if that person is too well defended.
If the offensive line blasts forward, the quarterback will hand or toss the ball to a running back who will try to get through or around the defense.
Every play is either a variation on those two options, or something tricky to make it look like one when it is actually the other. The more you watch the more you get to appreciate all the variations.
The other way to watch is to just pick one player, and watch what they do. Unlike most sports, almost all the movements are scripted. On a particular play a player might have a couple of options at most depending on what the other team is doing. Every player has a job though, even if it is just to force one of the other team to follow to get them away from something else that is going on.
The main exceptions to the scripted play are when there is a turnover, or when a receiver runs after catching the ball. Then it is much more like rugby or league (the main difference being that teammates can “block” - bash into other players to get them out of the road). The team I watch most are the Patriots - they run a high percentage of plays which are basically “get the ball to a gifted athlete with enough space to run and dodge”.
I like this guy’s Youtube channels. You can quibble about some of the details, but overall it’s really helpful for sports that I don’t know.
American football (NFL-specific)
See also:
Canadian football (99% the same, but useful to know)
American vs. Canadian contrast
Arena football (similar, but I don’t think most Americans know the difference, I certainly don’t)
To generalize for the OP, since he admits some knowledge of soccer and rugby (and for Dead Cat):
If you’re familiar with soccer and rugby, then you’re generally familiar with the two main brands of football that developed out of the 1800s: a game in which the ball cannot be picked up and carried (what English and Americans call “soccer”, from Football Association -> Association football -> Assoc. football -> “asoccer” -> soccer), and a game in which the ball CAN be picked up and carried forward, but must be passed forward by kicking (Rugby football, from the Rugby School in England which was one of the primary proponents of introducing that idea to football). Most football games around the world which trace lineage back to England fall somewhere along the continuum between these two.
Americans, predictably, found a third way to play the game. 
In American football, since 1906, the forward pass has been a legal play. The idea had been tried sporadically before. In 1906, a whole series of rule changes were adopted by colleges playing the game (birth of the NCAA, btw) to open up the game of gridiron football, which had become quite bloody, even quite deadly, due to the formulaic way in which it was played (and, arguably, the increasing use of forms of padding and helmeting to protect players). Gridiron football was already somewhat further down along the scale away from the "foot"ball game than even Rugby was, with the very scripted concept of scrimmages and downs and line of gain. With the forward pass (throwing the ball forward) legal, the need to kick the ball to advance was removed entirely. Now, in almost all situations, kicking the ball only occurs when possession is being surrendered to the other team in some fashion (without a try at a goal, by punting; with a try at a goal, by field goal; or to re-start play after a score, by kickoff). Thus, American football has stopped being “football” in any recognizable form, and has really become an outdoor form of handball.
One added aspect of the American (including Canadian) game is how the clock works. In almost all other footballs, the clock runs without stopping (rugby has some limited stoppages) for all of a half or quarter; time can be added as needed for injuries, etc. But in American football, the clock is stopped in a number of situations (usually having to do with either ball out of play or forward pass being incomplete). When the clock (which counts down) reaches 0:00, the game is over (with one or two limited exceptions related to penalties or extra-point tries); the referee does NOT have discretion to add time for things like injury, excessive celebration, etc. Thus, clock management becomes an important part of the game.
This is why a soccer game, which consists nominally of 90 min. of play, takes just under two hours to complete usually (15 min. half-time, plus 4-6 min. of added time for stoppages), whereas an American football game, which nominally takes only 60 min. to play, actually lasts in excess of three hours in most cases. We Americans do love to pay attention to things in very short increments. :rolleyes:
Football combines the two worst things about America: it is violence punctuated by committee meetings. – George Will
Thanks everybody for the great explanations! Especially Chronos for his in-depth discussion of the rules of the game, and enalzi for his link to the flowchart. I am absorbing all the wealth of information provided, and I will have questions 
As a matter of fact, I have a question – I understand that a punted ball cannot be touched by the team that did the punting until after it has touched a member of the other team. Is it allowable for a team to kick the ball on purpose towards a member of the other team so that it will “touch” him, bouncing off him, and then have a member of the punting team catch it and run with it? Would it ever make sense to do so?
Again, a big THANK YOU!!! to everybody who commented in this thread. As I said, later on I will have more questions ^.^
It would be pretty much impossible to do, and very risky. You would have to hit it just right so it wouldn’t hit your own players first. (You can see how a punt starts here: http://cdn.insidethepylon.com/wp-content/uploads/2015/01/CarReturn.jpg) Then, you would still need to recover the ball and go far enough to get a first down. Otherwise it would be a turnover on downs.
Punts are kicked on a very high arc, so it goes a long distance while taking a long time to do so.
In theory, this could be done, but it’d be pretty difficult for a punter to aim his punt that precisely.
A normal punt is a high, arcing kick – the goal is to both get distance and “hang time” to it, so that it moves the receiving team back as far as possible, while also giving members of the punting team time to get downfield. It’d be nearly impossible for a punter to aim for an opposing player with such a kick (as the player would have several seconds to just get out of the way).
If the punter attempted, essentially, a “line drive” punt, to aim for an opponent, it likely wouldn’t go very far downfield – and, so, if it didn’t work (that is, if the punting team wasn’t able to recover it after it bounces off of an opponent), the receiving team would wind up with very good field position.
When a punt does bounce off of a member of the receiving team, it’s almost always due to one of these two situations:
- The returner is trying to field the punt, but fails to cleanly do so
- A blocker for the returner isn’t aware of where the ball is, and it bounces off of him
Edit: ninja’d by enalzi!
If a punted ball hits a player on the receiving team before or near the line of scrimmage it is deemed a blocked kick, and either team can recover. But if the kicking team recovers the ball they must still pass the first down line or they give up the ball on downs.
It’s pretty hard to purposely kick the ball at someone past the line of scrimmage. It will most likely get blocked before it has a chance to travel very far, or the kick will be high enough that any receiving player can choose to get out of the way.
For what it’s worth, the name “football” (in any of its incarnations) doesn’t originally derive from kicking. It derives from the fact that the players are on foot, rather than mounted.
Interesting. Not that I doubt you, but do you have a cite for that?
There’s a reference to that explanation here. It doesn’t state anything definitive, though. It simply says that while the accepted etymology derives from it being played with the feet, an alternative etymology says it’s from being played on foot. There does not appear to be conclusive evidence either way, from what I can find.
Thank you both. So, in the (presumably fairly rare) situation where as a player on the receiving team, you can’t be sure of catching the punted ball cleanly, your best move is probably to let it bounce and just take possession of it where it eventually comes to rest (either out of bounds, or after being touched by a player on the punting side). Obviously in most situations it’s better to catch the ball and attempt to gain a few yards by returning the punt.
It’s actually not rare at all. That’s a pretty common strategy, especially if you are close to the goal line. That’s because of the touchback rule. If the ball bounces untouched into the end zone, the receiving team will get the ball at the 20 yard line.
Usually, the goal of the punting team is to get the ball as close to the end zone as possible without going in. They can try kicking it so it goes out of bounds just before the end zone (the coffin corner). Or the punting team can try and run down and stop the ball from going in the end zone (honestly, one of my favorite type of plays to watch)
Pretty much, yes. If the returner is able to get under the ball (but see the final paragraph below) and set up for a clean catch, he’ll nearly always try to do so. If members of the punting team are close to the returner as the ball approaches, he will usually signal for a “fair catch”, by raising a hand above his head – in a fair catch, if he catches the ball cleanly, he can’t advance it (his team gains possession at that spot), but the punting team is prohibited from hitting him once he catches it.
If he doesn’t signal for a fair catch, the punting team still must give him a chance to catch the ball, but the moment the ball touches the returner, members of the punting team may freely hit him (and this is where you see some of the most brutal hits in the game), which might separate him from the ball.
It’s also worth noting that most punt returns don’t wind up gaining much in the way of additional yardage – a return of 10 yards is a pretty good one, and it’s much more common to see the returner gain little or nothing during the return.
In the NFL, punt returners are usually instructed to not attempt to field the ball if it’s going to come down inside of the 10 yard line. Part of this is that, in fielding the punt, there’s a non-zero chance of a muff or fumble, and turning the ball over so close to your own goal line is essentially free points for the opponent. The other part is that, if the unfielded punt lands in the end zone, it’s a touchback (meaning that the receiving team gets possession, at the 20 yard line). So, members of the punting team will try to keep the ball from going into the end zone, and will try to down it as close to the goal line as they can, in order to give the receiving team very poor field position.
Looking at the stats for this year, here’s what happened with every punt:
Out of 2170 punts
937 were returned
603 were Fair Caught
268 were downed (i.e., not caught and didn’t go into the endzone or out of bounds)
213 went out of bounds
144 were touchbacks
5 were blocked