The three-point line was introduced in the NBA during the 1979-1980 season, revolutionizing the game and opening up new strategies for teams.

The original distance of the penalty kick in soccer was 12 yards, which was established in the Laws of the Game in 1891.

The volley, which allows players to hit the ball before it bounces, was introduced in tennis in the 1930s, adding a new dimension to the game.

The forward pass rule was introduced in American football in 1906 to increase scoring and make the game more exciting.

The instant replay system was first used in hockey in the 1990s to review controversial calls and ensure fair play.

The Designated Hitter (DH) rule was introduced in baseball in 1973 to increase offense and make the game more exciting.

The Metal Club Rule, introduced in the 1970s, allowed players to use metal clubs, which provided more distance and accuracy.

The offside rule in soccer was introduced to prevent cherry-picking, where a player would stand in front of the opposing team's goal and wait for a long pass.

The sin bin rule, where players are temporarily removed from the field for misconduct, was first introduced in rugby in the 19th century.

The serve clock in tennis was introduced in the 1990s to speed up the game and reduce time-wasting tactics.

The Coaches' Challenge Rule, introduced in the 1999 NFL season, allowed teams to challenge the referee's call on certain plays.

The Hawk-Eye system in tennis was introduced to review line calls and provide accurate decisions on close calls.

The golden goal rule, where the first team to score in extra time wins the match, was used in soccer to determine the winner in knockout matches.

The salary cap in professional sports was introduced to promote parity and prevent teams from spending excessively on player salaries.

The Traveling Rule in basketball, which defines the legal movement of a player with the ball, was modified to allow players to take two steps without dribbling.