Kokiri Sword

The Kokiri Sword is a recurring sword in the Legend of Zelda series. Although its design varies between appearances, it is always a short sword made for use by the diminutive Kokiri race, and thus, it cannot be used by adults.

The Legend of Zelda: Ocarina of Time
The Kokiri Sword, along with a Deku Shield, is needed for Mido to let Link pass through to the grove of the Great Deku Tree. It is the sword that Link uses as a child through the entire game.

At the Forest Training Center, Link finds the entrance to the Hole of Z, which he crawls through. He emerges into a maze-like area in which he finds a chest containing the Kokiri Sword. The description upon receiving the sword claims that Link is only borrowing it, making it one of the few items throughout the series that Link borrows from someone else.

The Legend of Zelda: Majora's Mask
Link wields the Kokiri Sword, which has been reforged and redesigned for unexplained reasons, at the outset of his adventure. Zubora and Gabora can reforge the sword into the Razor Sword, which has twice the power of the Kokiri Sword; however, it breaks after 100 strikes, thus reverting back into the Kokiri Sword. It may also be permanently reforged into the Gilded Sword, three times as powerful as the Kokiri Sword, if Link gives Zubora and Gabora a Bottle of Gold Dust.

Super Smash Bros. Melee
Along with the Deku Shield, the Kokiri Sword is Young Link's primary weapon.

In the manga
Mido has the Kokiri Sword and joins Link in the Great Deku tree to fight Queen Gohma. However, Mido is frightened and just stands in the way, forcing Link to save him repeatedly. He does distract Gohma, giving Link a chance to attack using the Fairy Slingshot. After the fight, Link takes the sword to make a shield out of the Deku Tree's remains. Link wants to return it afterward, but Mido refuses to take it.

Link takes the sword out of Kokiri Forest and uses it until he pulls the Master Sword from the Pedestal of Time. The sword is never shown again.

Kokiri-Schwert Espada Kokiri コキリの剣