Goalkeeper, often shortened to keeper or goalie, is one of the major positions of association football. It is the most specialised position in the sport.
The goalkeeper's primary role is to prevent the opposing team from successfully moving the ball over the defended goal-line (between the posts and under the crossbar). This is accomplished by the goalkeeper moving into the path of the ball and either catching it or directing it away from the vicinity of the goal line.
Within the penalty area goalkeepers are able to use their hands, making them (outside of throw-ins) the only players on the field permitted to handle the ball. The only time when a goalkeeper is not allowed to use their hands inside their box is when a field player of their own team does a direct pass.
The most common way to know that it is a direct pass, and not an indirect pass, is when the field player has control of the ball. Goalkeepers are allowed to pick up the ball during an indirect hit from a teammate (headers, chest, knee thigh, and when the ball bounces off the player). Goalkeepers usually perform goal kicks, and also give commands to their defense during corner kicks, direct and indirect free kicks, and marking. Goalkeepers play an important role in directing on field strategy as they have an unrestricted view of the entire pitch, giving them a unique perspective on play development.
If an attacker on the opposing team obstructs the keeper from catching or saving the ball, for example, in a corner, it will normally be a free kick.