Dashavatara of Lord Vishnu is one of the most popular concepts of Hinduism, which has been widely worshiped by the Hindus in one or the other form.
According to Hindu mythology, Bali Padyami commemorates the victory of god Vishnu in his dwarf incarnation Vamana, the fifth incarnation of the Dashavatara (ten major incarnations of Vishnu) defeating Bali, and pushing him to the nether world.