In American football, downs are the fundamental characteristic of the sport which separates it from others.
A down is essentially another word from an attempt, and when a team has the ball they have four attempts - or downs - to advance the ball 10 yards.
If the ball is advanced 10 yards in four downs or fewer, a new set of downs is awarded to the team with the ball to once again try to move the ball 10 yards.
When watching or listening to a game, you will hear that a team on offense is at “1st and 10” or “3rd and 3”.
When such phrases are used, the first part of the expression is an indication of what down it is and the last number shows how many yards are still needed to earn a fresh set of downs.
If a team on “2nd and 6” progressed more than six yards on the play they will have a new set of downs, however if they only gained five yards they would be on “3rd and 1”.
If a team is unable to progress 10 yards, the team on defense will win possession of the football from the spot the fourth down ended.
As a result, on fourth down teams will often opt to not run a traditional play and instead turn to their kicker or punter.
If they are too far away from the defensive team’s end zone for a field goal to be possible, teams will often punt the football to give the opposition the worst possible starting field position.
However if the team on offense is in opposition territory, they will often attempt a field goal to try score three points.