A touchdown (abbreviated as TD) is a scoring play in gridiron football. Whether running, passing, returning a kickoff or punt, or recovering a turnover, a team scores a touchdown by advancing the ball into the opponent's end zone. In American football, a touchdown is worth six points and is followed by an extra point or two-point conversion attempt.

The scoring team is also awarded the opportunity for an extra point or a two-point conversion. Afterwards, the team that scored the touchdown kicks off to the opposing team, if there is any time left in the half. In most codes, a conversion is not attempted if the touchdown ended the game and the conversion cannot affect the outcome.

The officials' hand signal for a touchdown is both arms extended vertically above the head, with palms facing inward—the same signal used for a field goal or conversion.

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