The post-classical Yoga includes all versions of Yogas including Hatha and Tantra Yogas. The proponent of modern Yoga (Post-classical yoga) is Swami Vivekananda who introduced the Yoga in USA in late 1800 AD. He attended the Parliament of Religions in Chicago in 1893 and gave sermon on Yoga. He traveled throughout USA and propagated Yoga to the lively acceptance of Americans.
Swami Paramahmsa Yogananda was yet another noteworthy exponent of Yoga.
Later, Swami Sivananda, who made Himalaya his home, became the exponent of Yoga and introduced five modified principles to the Yoga. They are: (1) Savasana (proper relaxation), (2) Asanas (proper exercises), (3) Pranayama (proper breathing), (4) Sasyahar (proper vegetarian diet), and (5) Dhyana (proper meditation). He has authored over 200 books on Yoga and Philosophy.