Noh, the oldest remaining theater art in the world, is known for its simple and strictly defined movements, for its use of beautiful, artistically crafted masks, and for its unique form of dialogue reminiscent of a bygone age. Noh drama reveals universal human frailties, especially the ephemeral nature of love, and has a strong emotional appeal for the audience. Noh also weaves into a story the inner workings of the human heart at each moment, while conveying inner tension and spiritual strength. A program of Noh always includes Kyogen, comedy plays that taught morality to the common people in medieval times and provided comic relief from the serious tone of the Noh plays themselves. Noh and Kyogen are performed at the Osaka Nogaku-kaikan Theater and the Otsuki Nogaku-do Theater; every July, Noh plays are also shown after dark by torchlight in the Osaka Castle Nishinomaru Garden.