A quarterback (often abbreviated as QB) is considered the most important position in American Football. The quarterback is usually responsible for initiating offensive plays, calling sometimes changing the coach's play by calling an "audible" after the players have lined up.
The most important traits for a quarterback are leadership, thriving under pressure, and a strong, accurate throwing arm. Quickness and agility are becoming increasingly important, in order to run occasionally for a first down and to avoid being "sacked". Throwing interceptions can be disastrous and single-handedly cause a loss for the team.
Due to their high visibility and level of importance, quarterbacks are usually the "star players" of a team, earning a large salary and lots of public attention.
Past prominent quarterbacks include Joe Montana and Terry Bradshaw, who each won 4 Super Bowls for the San Francisco 49ers and Pittsburgh Steelers, respectively. Current prominent quarterbacks include Tom Brady (4 Super Bowl wins), Ben Roethlisberger (2 Super Bowl wins), Eli Manning (2 Super Bowl wins), Peyton Manning, Aaron Rodgers, and Drew Brees (1 Super Bowl win each).