American football basics
American football rules: downs, scoring, field and possession
A practical guide to the common structure of American football: 11 players per side, four downs to gain 10 yards, how scoring works and how possession changes.
Teams, possession and the snap
American football is played with 11 players from each team on the field. One team has possession on offense while the other defends. Most plays begin with a snap, and possession can change after a score, punt, turnover or failure to earn a new series of downs.
Four downs to gain 10 yards
The offense normally receives a series of four downs to advance at least 10 yards. Reaching the line to gain awards a new first down; failing by the end of fourth down normally gives the opponent possession unless the play ends with a kick or another change of possession.
How scoring works
A touchdown is worth 6 points, a field goal 3 and a safety 2. After a touchdown, a team may attempt a try for additional points. Exact try and overtime procedures depend on the competition.
Field and league differences
The field between the goal lines is 100 yards long, with a 10-yard end zone at each end. NFL and NCAA football share the core structure but do not use identical timing, kickoff, overtime, replay and enforcement rules, so ODDSNEX keeps their series-specific details separate.