Yoga has roots in India. The foundational text for yoga is the Yoga Sutras of Patanjali. Yoga came to the attention of the western public in the mid 19th century along with other topics of Hindu philosophy. The first Hindu teacher to actively advocate and disseminate aspects of yoga to a western audience was Swami Vivekananda, who toured Europe and the United States in the 1890s.
Nearly all types of hatha yoga practices include asana, pranayama and savasana. The physical asanas of hatha yoga have a tradition that goes back to at least the 15th century, but they were not widely practiced in India prior to the early 20th century.
The more classical approaches of hatha yoga, such as iyengar yoga, move at a more deliberate pace, emphasize proper alignment and execution and hold asanas for a longer time. They aim to gradually improve flexibility, balance, and strength. Other approaches, such as Ashtanga or power yoga, shift between asanas quickly and energetically. Contemporary approaches to yoga invite students to become their own authority in yoga practice by offering principle-based approaches to yoga that can be applied to any form.