Yama is the lord of Death and ruler of the Hell. He is one of the eight principal rulers of the eight directions. He rules over the direction of South. He is referred to as Dharma too. He was the son of Sun god. He was the divine father of Yudhishthira.
Yama's duty is to award results of good and bad deeds done by the mortals . In the Mahaabhaaratham, he tested Yudhishthira once in the form of a Yaksha when the Paandavas were in the forests and again during their renunciation walk, by following them to the end in the guise of a dog.