Like Nayru, Din is actually two different characters: Din, the Goddess of Power; and Din, the Oracle of Seasons.
Din Goddess of Power is one of the three Golden Goddesses. She single-handedly created the landscape of Hyrule. She is associated with the color red, and represents the elements of earth and fire. She is best known for Link's magic spell Din's Fire, which when cast, emits a three dimensional semicircle of fire out of Link, burning all nearby enemies to a crisp. Din is one with the Triforce of Power, the piece that Ganon takes from the Sacred Realm. Din appears in The Legend of Zelda: Ocarina of Time, The Legend of Zelda: Collector's Edition, and The Legend of Zelda: Ocarina of Time / Master Quest.
Din, also known as the Oracle of Seasons, is a character in The Legend of Zelda: Oracle of Seasons. Din controls the passing of the four seasons, so when captured by General Onox, she is no longer able to maintain their balance. During the game the seasons shift uncontrollably until Link obtains the Rod of Seasons from the Temple of Seasons. Din adorns the disguise of a dancer in order to avoid detection from General Onox. This plan fails as Onox sees right through the guise, and temporarily imprisons her in a crystal. With Din rendered useless, and the Temple of Seasons underground, unadulterated chaos rampages throughout Holodrum.
In The Minish Cap, she appears alongside Farore and Nayru.