The NFL’s rules have continued to evolve since football’s earliest days — always changing to protect the league’s integrity and make the game fairer, safer and more entertaining. Today’s rules have come about through testing, analysis and careful deliberation, and as a result the game has evolved into the sport beloved by millions today.

Learn more about the evolution of the NFL rules — from the days when a forward pass was permitted only once during a series of downs to the high-octane game today.