Trebuchets are seige weapons from Medieval times. While used extensively in Europe ( and extremely popular during the Crusades ) they were found throughout the Middle East and China ( where they were invented ).

Essentially a trebuchet is a first class lever ( like a large teeter-tooter ). You have a load ( in the form of a stone or a dead cow ) on one end, the balance point ( fulcrum ) in the middle and the effort ( usually a group of men pulling in unison or a large counterweight ) on the other end. Trebuchets were extremely efficient, accurate, easy to build, and much more stable than their simple catapult cousins. In the right circumstances, one man could operate a trebuchet freeing others for the battle. Using a winch to pull down the throwing arm, one fellow could load and launch in a short amount of time! One recorded account of a seige suggested the trebuchet shot in the air was so thick, a hat held over the battlement would have been holed!

In contrast are "catapults." These relics are a third class lever ( like a baseball bat )...with a load on one end, the effort in the middle ( often in the form of tightened ropes ) and the pivot on the other end. When released, the throwing arm would carry the load for a distance until abruptly stopped by a bar. Inertia would carry the load to its intended target. Catapults were famous for blowing up, as all the energy is moving forward until it rams into the stop bar! This would cause the catapult to jump around ( one source estimated that a catapult crewman died every 5 throws when it bucked! ).

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