Good. Maybe you can educate me. I'll be the first to admit that I don't know much about Soccer. Trying to learn though..
Well, here's what makes football different from other sports. In sports like handegg (NFL), basketball, hockey, and rugby, it's basically about brute strength. Football is more about finesse. Let's first take a look at a few similar things.
Similar:
You do see a lot of man coverage and zone coverages in both defensive styles. In football, man coverage is referred to as "marking" your opponent. This is particularly critical in set pieces (which will be explained further later). If you fail to mark your man, then it becomes a very daunting task for the keeper to try to cover the mistake, otherwise it's a goal. Thus, communication between the defender and the keeper is important. Similarly, a corner must be able to mark the WR successfully before the QB can see any slight opening. If he's having trouble, then he can request the safety's help, so communication is critical. If it fails, then the defense will usually give up a TD. After all, players like Frazier are basically the goalkeeper for the defence.
Offensively, you can choose to pass short, medium, long, or a mixture of them in both sports. In football, the passing is critical to try and find your open players along with moving the ball, which is the same as handegg in this regard. Obviously, the open player has a better chance to score.
Now, to understand offside in football, offside is called when the attacking player receiving a pass is beyond the last defencive player on a play that is not a corner kick or a throw in. Thus, when you are watching the WC and you see the side official raise his flag, that's usually the problem.
Now, here's where the finesse of football comes in:
Here's are some good tackles:
As you can see, the goal is to dispossess the attacking player, which is a bit like trying to force a fumble. You're goal isn't to take the chap down so much as it is to strictly go after the ball. Where you run into trouble is when you start throwing players to the ground or trying to take the player down such as sliding into the player's leg. Obviously, that's a dangerous way to defend, and making that sort of tackle will get you booked (Yellow card or red card depending on the severity of the foul).
Additionally, the passing is rather finesse in football. The crosses and slide passes (when you pass it to the player just to the left or right of you near the goal) are designed to pass the ball in from the wing into the centre of the pitch. As you can imagine, this has great effect if the receiving player strikes it properly. Thus, the passing is a tad more finesse in that it takes more art than it does brute strength to make these passes successful, and then turn it around for the shot.
If you have any additional questions about football, please feel free to ask me.