In association football, a ghost goal is either a goal wrongly awarded despite the ball not having crossed the goal line, or a goal wrongly not given despite the ball having crossed the line. In an attempt to combat ghost goals, rules allowing goal-line technology (GLT) were passed by the International Football Association Board in 2012 and have consequently been introduced for some football competitions, including the FIFA World Cup, FIFA Club World Cup and Premier League. The video assistant referee (VAR), introduced in 2018, provides an alternative system to GLT, and is cheaper to introduce and operate than the FIFA qualified GLT systems.

In association football, goal-line technology is the use of electronic aid to determine if a goal has been scored or not. In detail, it is a method used to determine when the ball has completely crossed the goal line in between the goal-posts and underneath the crossbar with the assistance of electronic devices and at the same time assisting the referee in awarding a goal or not. The objective of goal-line technology (GLT) is not to replace the role of the officials, but rather to support them in their decision-making. The GLT must provide a clear indication as to whether the ball has fully crossed the line, and this information will serve to assist the referee in making their final decision.