From Minecraft Wiki
Weapons may refer to:
Sword - A craftable weapon used to damage mobs or other players.
Bow - A ranged weapon that fires arrows to deal damage.
Arrow - An item that can be fired with Bows or Dispensers to deal damage.
Damage Potions - Potions that can be used to deal damage to players.
Note: This video states the swords, bows and arrows are the only weapon. This was before the introduction of splash potions, meaning now there are four types of weapons in the game rather than three.