The three-point line is the arc painted on the court beyond which a made field goal counts for three points instead of two.
The line is the single rule change that most reshaped the sport's geometry. The NBA adopted it for the 1979 to 1980 season, borrowed from the ABA, which had used a three-point arc since its founding in 1967. The distance has shifted over the years: the league shortened the line to a uniform 22 feet for three seasons in the mid 1990s, then restored the longer arc, which now measures 23 feet 9 inches at the top and 22 feet in the corners.
A shot counts for three only if the shooter releases it with both feet clearly behind the line, and officials review borderline plays by video, checking whether a toe was on the paint of the arc itself. Stepping on the line turns a celebrated three into a long two, a distinction that decides quiz questions and real games alike.
Strategically, the line moved shot selection for the entire sport. Shots from just inside the arc became the worst value in basketball, offences reorganized around spacing the floor to the line, and Stephen Curry's career, built on range several feet beyond it, is the clearest measure of how completely the line won.
In use"He stepped behind the three-point line and launched it before the defence could set."