Kokiri Sword

The Kokiri Sword is the default sword Link possesses in both Ocarina of Time and Majora's Mask. It is also the weakest sword in both games. In Ocarina of Time it is the only sword he can wield as a child, and when he is an adult he uses the Master Sword instead. In Majora's Mask Link is able to upgrade the Kokiri Sword to the powerful (albeit breakable) Razor Sword and then upgrade again into the unbreakable Gilded Sword by taking it to the blacksmiths in Mountain Village. The hilt and guard of the Kokiri sword changed from Ocarina of Time to Majora's Mask.

Trivia

 * The Kokiri Sword appears, in its Ocarina of Time incarnation, as the blade wielded by Young Link in Super Smash Bros. Melee.