sentence: Catapults use weights and levers to send the rocks or other things into the air.
sentences_before: A 'catapult' is a type of machine used as a weapon to shoot rocks or other things that would cause damage to something else.
sentences_after: They are simpler than other modern weapons and not useful in modern warfare. Catapults were common in the past, especially the Middle Ages.
concept_name: catapult
headings: Catapult
categories: Weapons