A cornerback is a defensive player in football. The cornerback guards against the offensive team, in particular, any player that may catch the football on the offense, such as the wide receivers, tight ends, or running backs. The cornerback is one of three positions considered to be defensive backs (DB), the other two being the free safety (FS) and the strong safety (SS).
Most of the time, cornerbacks line up opposite of wide receivers on the offense and guard them to prevent a completed pass. It can be a challenging position to play as it can be very hard to guess where a receiver or tight end may go to catch a pass. Cornerbacks line up in what is called the secondary (as in the second line of defense). If an offensive player can get past the secondary, they will most likely score.
Cornerbacks work to create turnovers on the field. They step in wherever needed to stop the offense, whether that be making a tackle or trying to deflect an incoming pass. Cornerbacks should be large in size but also light on their feet. Being a cornerback means having many versatile roles, which is why it is one of the most challenging positions to play on any football team. Cornerbacks should be natural leaders of the defense and be able to decide their next move after taking a quick glance at the field.