I WONDER - How Were Castles Defended?

Castle defenders needed to be both smart and brave, utilizing the high walls to pour boiling liquids or shoot arrows at attackers. They worked diligently to repair any damage and countered tunnels if attackers got too close. In close combat, they used swords and shields to fend off enemies.

What actions did defenders take to repair damage to the castle?

What types of combat were used by defenders against attackers?