Softball is a team sport popular especially in the United States. It is a direct descendant of baseball and the rules of both sports are substantially similar; baseball is sometimes referred to as hardball to distinguish the two. Softball was invented by George Hancock in Chicago, Illinois. The first softball game was played using a rolled up boxing glove as a ball and a broomstick as a bat.

Softball is played between 2 teams on a large field, composed of a dirt infield which contains the "diamond" and running areas, and a grass outfield. There are 4 bases on the infield (first base, second base, third base, home plate); the bases are arranged in a square and are typically 45 to 65 feet apart. Near the center of this square is the pitcher's circle, and within the circle is the rubber, a small flat rectangular area. The object of the game is to score more runs (points) than the other team by batting (hitting) a ball into play and running around the bases, touching each one in succession. The ball is a sphere of light material, covered with leather or synthetic. It is 10 to 12 inches (or rarely, 16 inches) (28 to 30.5 centimeters) in circumference.

The game is played in a series of innings, usually seven to nine. Youth leagues sometimes have 6 innings. An inning is one series of both teams playing offense and defense. Each inning is divided into a top half and a bottom half indicating which team is playing which role. The offense bats and attempts to score runs, while the defense occupies the field and attempts to record outs in a variety of ways. After the defense records 3 outs, the half inning is over and the teams switch roles.

To start play, the offense sends a batter to home plate. The batting order must be fixed at the start of the game, and players may not bat out of turn. The defense's pitcher stands atop the rubber and throws the ball towards home plate using an underhanded motion.

Offensive strategy is fairly straightforward, revolving around hitting the ball to enable the batter to reach base safely and to advance the base runners towards home plate. Defensive strategy can be more complex, with particular situations calling for different positioning and tactical decision making. For both sides, there can be a trade-off between outs and runs: the offense can sacrifice a batter to advance runners, while the defense may allow a runner to score if the remaining runners can be put out in a double play.