Quidditch is a Wizarding sport played on a broom. It is usually played between two teams in a field or stadium with six goal posts (three for each team). There are 14 people on the field at one time, 7 for each team. There are 3 Chasers who pass around the Quaffle, and try to get the Quaffle through the goal posts. Known Chasers are Angelina Johnson, Demelza Robins, Ginny Weasly and Katie Bell (Gryffindor team). There are 2 Beaters. They stop the Bludgers from hitting other players with bats. Known Beaters are Fred and George Weasley as well as Jimmy Peakes and Ritchie Coote (Gryffindor team). There is 1 Keeper. The Keeper stops the chasers from throwing the Quaffle in through the goal posts. Known Keepers are Oliver Wood and Ron Weasley. There is 1 Seeker. The Seeker needs to catch the Golden Snitch to give their team 150 points and to end the game. Known Seekers are Harry Potter (Gryffindor), Draco Malfoy (Slytherin), Regulus Black (Slytherin) Cedric Diggory (Hufflepuff), Cho Chang (Ravenclaw), and Charlie Weasley (Gryffindor).
According to the film adaption of Harry Potter and the Philosopher's Stone, James Potter is known to be a Seeker for the Gryffindor Quidditch Team. According to J.K. Rowling, James Potter was a Chaser.