Yoga is known as Brahmavidya (knowledge of the supreme spirit).In yoga terminology, non-violence, truthfulness, non-stealing, celibacy and nonpossessiveness are called 'yamas' (moral restraints) and purity, contentment, self-study, worship of God, and austerity are called 'niyamas' (moral observances). Restraints and observances (yama-niyama) are the strong-hold of yoga or religion. Without them, the preservation of yoga or religion is impossible. Wise yogis have described these restraints and observances as the great universal codes of conduct. The principles of these restraints and observances form the greatest part of social religion. Lord Siva and Lord Krsna are are the two urdhvareta yogis (urdhvareta saint who has done penance over the restraint of the sexual organ is not a human being but a god). They are the first propounders of Brahmavidya (knowledge of the supreme truth). What the sadhaka should do first of all to become an urdhvareta is shown by Sri Krishna in the Bhagavad Gita, "Thus O Bharatsrestha! First restrain the senses and decisively abandon this evil lust which destroys knowledge and realization."
There cannot be different types of yoga. But there are differences in the natures of different sadhakas, differences of background, differences of methods used for spiritual practice; differences in fitness for practice, and many other differences.The stage of yoga during which the yogi acquires divine body is defined by the scriptures as sarupya mukti; emancipation during which the seeker acquires the sought after form. After attaining that liberation, i.e. after transcending that stage, the yogi attains sarstya mukti in the fourth stage of yoga. In sarupya mukti, the yogi achieves a form identical with that of Sri Hari (the Lord) and in sarstya mukti, he achieves all the powers of the Lord. In this manner, the yogi resembles the Lord.