
The Triforce of Courage is one of the three parts of the Triforce, and is the triangle on the right, as seen in Ocarina of Time. It embodies courage, has been represented by the color green, and is tied to the Goddess of Forests and Courage, Farore. The Triforce of Courage was the piece of the Triforce that entered Link after Ganondorf entered the Sacred Realm and touched the Triforce, trying to harness its power for himself.
Either Link I or Link II later shattered it after he left Hyrule, and the Royal Family hid the pieces in Hyrule. The Hero of Winds afterwards went questing to gather the shards of the Triforce. The Triforce of Courage was recombined with its brothers, the Triforces of Power and Wisdom at the bottom of the sea at Old Hyrule Castle. It was then carried to New Hyrule and stored in Princess Zelda as a whole, until seperated much later on.
In Phantom Hourglass, the Fairy of Courage, Ciela, is a kind of representative of the Triforce of Courage, as well as Link III's companion throughout the adventure.
Note: For more about the Triforce see Triforce, Trueforce, Triforce of Wisdom, and Triforce of Power.