A term referring to the rectangular area on the court contained within the key. The key is the area that encompasses the middle of the floor underneath the basket. It is often shaded, which explains the origin of the word, and always has a semi-circle attached on the short side opposite the basket. The paint refers to the area only within the rectangle, excluding the semi-circle. The four corners of the paint are known as the high post (two top corners) and low post (bottom two corners, closer to the basket).
The paint is the most valuable position on the floor for an offensive player because of its proximity to the basket. A player receiving the ball in the paint will have a higher percentage of success, whether it is to score or pass, because he will either have an easy shot, or he will potentially be swarmed by defenders, leaving a teammate open. For this reason coaches design lots of plays to get the ball into the paint on offense and out of the paint on defense. Furthermore, there are rules at every level of competition which govern the behavior of players inside the paint, the most well-known of which is the "three-second rule." The three-second rule prevents an offensive player from standing in the paint for more than three seconds.