Quiz bowl is a generic term for a team game done at high school and college level. Variations include College Bowl, Scholastic Bowl, and just plain Quiz Bowl.
During a quiz bowl tournament* there are several rounds (Usually involving going up and down 2-3 flights of stairs every 20 or so minutes) and each team gets a tossup, no confering between teammates is allowed, and one loses points if they answer incorrectly while the moderator is reading. After this only the other team can answer. However, if that person gets it correct, they get a bonus that is worth much more and is often on a broader topic, confering between teammates is allowed here. Bonuses are where most points come from. A round is split into approximately 2, 9 minute intervals where you can make subsitutions once when the 1st interval ends.
Quiz bowl tournaments are rather sporatically setup around the Los Angeles area. I joined my school's team because I know a load of infinately random stuff, and it shows. If you join it and expect to get a trophy at each event, you will be sorely disappointed. It is quite hilarious to get quiz bowl prizes, usually consisting of Calvin and Hobbes books to The White Trash Cookbook (These were prizes at a USC tournament).
* I'm going by NAQT standards, so if it differs, please tell me!