A position on offense that lines up in the backfield and is primarily responsible for running with the football. The tailback is also responsible for catching the ball out of the backfield, and helping to block on passing plays. The tailback will most often line up behind the quarterback, although will line up next to the quarterback in shotgun formations. Tailbacks are often faster and more agile than other backs, and will have the highest rushing statistics on a team under most circumstances.
The tailback is the primary weapon in a team's rushing offense. A tailback must be able to carry the ball with both speed and power. Most running plays will be designed to either handoff or pitch the ball to the tailback, who will then attempt to find a hole created by his offensive line to advance the ball downfield. Good tailbacks will carry the ball many times throughout a game. A tailback can also be responsible for catching the ball out of the backfield on passing plays, or staying back to help protect the quarterback from the opposing pass rush.