Definition
A ballista is an ancient military engine resembling a large crossbow, used for hurling stones or darts. It uses torsion power, twisting ropes or sinews to generate force. Think of it as an ancient artillery piece. Unlike catapults which used levers, ballistae used tension. Ballistae were accurate and powerful for their time. The Roman army frequently used ballistae during sieges and battles. They represent ancient engineering and military strategy.