Sword and shield are defensive weapons, blocking will transform the damage received to hunger. Can also be used to parry attacks dealing extra damage.
As of a more recent update, Sword & sheild sheilds now DO render in third person on the player, and all can be found in dungeon chests, except for the ones where the sword is neither iron nor diamond.
Enchantments:
Block resistance: reduces the hunger consumed blocking.
Parry damage: increases the extra damage dealt parrying