Yoga-like practices were first mentioned in the ancient Hindu text known
as Rigveda.[7] Yoga is referred to in a number of the
Upanishads.[8][9][10] The first known appearance of the word "yoga" with
the same meaning as the modern term is in the Katha Upanishad,[11][12]
which was probably composed between the fifth and third centuries
BCE.[13][14] Yoga continued to develop as a systematic study and
practice during the fifth and sixth centuries BCE in ancient India's
ascetic and Śramaṇa movements.[15] The most comprehensive text on yoga,
the Yoga Sutras of Patanjali, date to the early centuries of the Common
Era;[16][17][note 1] Yoga philosophy became known as one of the six
orthodox philosophical schools (Darśanas) of Hinduism in the second half
of the first millennium CE.[18][web 1] Hatha yoga texts began to emerge
between the ninth and 11th centuries, originating in tantra.
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