Basketball is a fairly simple sport, comprised of a rectangular court and a hoop at either end. The goal of the game is to have the most points at the end of the game. Each team has five players on the court at any given time.
Each quarter is 12 minutes long, totalling a 48 minute game. The game clock counts down, not up. The clock will stop for certain things, like a ball moving out of bounds (outside of the lines of the court), or for free throw shots. There is a halftime in between the 2nd and 3rd quarters.
Each team has five players on the court, but can have up to 15 players on their team (also known as a roster), and they can be substituted in for each other as the coach sees fit. However, only when the game clock stops. A player can exit the game and then return later, but must check in with the game scorers (at the scorer’s table) and with the referee before doing so.
The court is a rectangle with a hoop mounted in the middle of each short end. The usually-solid colored rectangle underneath the hoop is called “the key,” but it’s also known as “the paint.”
The end of the key opposite its hoop (aka “the top of the key”) is the free throw line. Penalty, or free throw shots, are made from here.
The half circle underneath the basket in the key is the “restricted area,” where players can only stand for three seconds before they are called for a foul. The marks on either side of the key show players where to line up on free throws. The thicker marks close to the basket are called “the blocks.”
The wider half circle that encompasses the key and the free throw line is the three-point line.
The line in the middle of the court is called the “half court line.”
The lines that border the court are called sidelines. The boundaries below the basket are also called baselines.
The act of throwing a basketball into the hoop is called a “shot,” “field goal attempt,” or “shooting the basketball.” When a player puts the ball in the hoop at the rim, that’s called a dunk (which is where the term “slam dunk” comes from, like in the GIF above). A dunk is still a shot, but a shot is not always a dunk.
Shots made from outside the three-point line are worth three points.
Shots made within the three point line during the course of play are worth two points.
Shots made from the free throw line, while shooting after a foul has been committed, are worth one point.
*Measurements are based on professional standards. This may differ from league to league.