Basics
Basketball is a game, basically, where you need to get the ball into the opposing team's basket, and then don't let them do the same to your's.
Defense
There are two kinds of defnense, man-to-man, and zone.
Man-to-man
Man-to-man is where each defensive player is assigned a specific man to guard, but you keep your eye on the ball too. Zone
Zone is where each player guards a specific area on the court.In zone there are the guards, the forwards, and the center. The guards are up near the top of the zone, and the forwards are near the bottom. The center takes the middle of the zone, making sure no one penetrates.
Offense
There are many attributes to offense, but the basic idea is to score a basket by putting the ball into the opposing team's hoop. There are two main ideas in offense, passing and shooting.
Passing
Passing can be a bounce pass or chest pass. A bounce pass will hit the floor before it gets to your teammate, and is harder to steal. A chest pass won't hit the floor at all. Shooting
With shoting, every shot is unique. No one has the same form, the same way of shooting the ball. There is something called the three point line, because if you make a shot from beyond it, then your basket counts for three points, instead of the normal two. Also, if the opposing player physically interferes with your shot in any way, then the referee will call a foul. This is called a shooting foul. You then get free throws, from the foul line. If you miss the shot, you get as many free throws as the shot was worth, because they count as one. If you make the shot, you get the points, plus a free throw shot.
The professional basketball in the USA is the NBA.