Ribbon

The Ribbon is an item that has been seen twice in the Legend of Zelda series, serving two different purposes.

Link's Awakening
The Ribbon in serves as the second item in the game's Trading Sequence. In Mabe Village, the mother of the quadruplets says that her baby wants a Yoshi Doll, which can be won in the village's Trendy Game. When Link gives her the doll, he will be rewarded with the Ribbon. The Ribbon then has to be exchanged to an ill-conceited Chain Chomp, who lives in a side room of Madam MeowMeow's house, for a can of Dog Food.

Because part of the Trading Sequence is required in order to progress further in the game, it is required that Link obtains the Ribbon and trades it.

Oracle of Seasons
In Oracle of Seasons, Link must give the Ribbon to a Subrosian celebrity named Rosa so he could "date" her. This is necessary to obtain a Key which allows Link to enter the Summer Tower of the Temple of Seasons.