In professional American football, a penalty flag is a bright yellow cloth thrown onto the field by a game official (referee) to signal that a rule violation has occurred. The act halts play and initiates a review by the officiating crew. For example, if a defensive player illegally makes contact with a receiver before the ball is thrown, the nearest official will typically throw the flag to indicate defensive pass interference.
This signal is crucial for maintaining fair play and upholding the integrity of the game. It ensures that infractions are addressed, preventing teams from gaining an unfair advantage. The use of flags dates back to the late 19th century, providing a more visible means of signaling penalties compared to earlier methods like whistles or verbal calls. Its implementation contributed to standardizing the rules and improving the consistency of officiating across different games and eras.
