The corner kick rule is one of the most important rules in football. Corner Kicks provide a good scoring opportunity for the side. When the ball crosses the goal line while still in play, without a goal being scored, and after it was last touched by a member of the defending team, play is restarted with a corner kick. The kick is taken from the corner of the field of play closest to the place where the ball crossed the goal line
When is a Corner Kick Awarded?
When the ball completely crosses the goal line outside of the goal frame after being last touched by a member of the team defending that end of the field, a corner kick is given.
How is a Corner Kick Taken

The referee first raises the flag signaling that a corner kick is awarded. The ball is kept on the quarter circle from the corner flag post inside the field of play.
Before the ball enters play, all opposition players must be at least 10 yards (9.15 meters) away from the corner area. To help the referee enforce this rule, optional markings may be made on the field.
The attacking team might score directly from the corner kick, but it is very rare. The player taking the corner kick usually plays it near the goalkeeper’s playing area and the player of the attacking team scores by heading the ball.
How does the attacking team defend a corner?
Man Marking

In this technique, the players of the defending team stop the attacking team from scoring a goal. The players usually mark the best player from the attacking side and stop him from scoring a goal. The main objective is to head the ball away from the danger and the players from the attacking side.
Forming a wall

To force the ball to be played to a location that can be more readily defended, the opposing side may decide to build a wall of players. The requirement is that defensive players stay at least 10 yards away from the ball until it enters play.
Putting Players on the Post

To protect the goal in addition to the goalie, the defensive team may additionally choose to direct a player to position himself beside goalposts. The idea behind situating a player next to a goalpost is to protect more of the goal area and make up for the positioning and reach of the goalkeeper.
-- Advertisement --Types of Corner Kicks
In swinging corner

In this kick, the ball curls in towards the goalpost. The left-footed player takes the corner on the right side and the right-footed player takes the corner on the left side.
Also
Out-swinging corner

Here, the ball curls away from the goalpost. The left-footed player takes the corner on the left side and the right-footed player takes the corner on the right side.
Straight Corner

In this type of kick, there is no particular lateral movement on the ball. The ball comes in straight without any deviation.
Clipped Corner

In a clipped corner, the ball travels a higher trajectory with a reduction of speed. Players who are attacking this cross have to generate a high pace on the ball to score a goal.
Short Corner

The corner taker passes the ball to a player which is closer to him 5-10 yards away. The attacking team tries to regain possession of the ball to create a meaningful attack and penetrate through the opposition’s defense.
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