<P> Tantra is a genre of yoga that arose in India no later than the 5th century CE . George Samuel states, "Tantra" is a contested term, but may be considered as a school whose practices appeared in mostly complete form in Buddhist and Hindu texts by about 10th century CE . Over its history, some ideas of Tantra school influenced the Hindu, Bon, Buddhist, and Jain traditions . Elements of Tantric yoga rituals were adopted by and influenced state functions in medieval Buddhist and Hindu kingdoms in East and Southeast Asia . </P> <P> By the turn of the first millennium, hatha yoga emerged from tantra . </P> <P> Vajrayana is also known as Tantric Buddhism and Tantrayāna . Its texts were compiled starting with 7th century and Tibetan translations were completed in 8th century CE . These tantra yoga texts were the main source of Buddhist knowledge that was imported into Tibet . They were later translated into Chinese and other Asian languages, helping spread ideas of Tantric Buddhism . The Buddhist text Hevajra Tantra and Caryāgiti introduced hierarchies of chakras . Yoga is a significant practice in Tantric Buddhism . </P> <P> The tantra yoga practices include asanas and breathing exercises . The Nyingma tradition practices Yantra yoga (Tib . "Trul khor"), a discipline that includes breath work (or pranayama), meditative contemplation and other exercises . In the Nyingma tradition, the path of meditation practice is divided into further stages, such as Kriya yoga, Upa yoga, Yoga yana, Mahā yoga, Anu yoga and Ati yoga . The Sarma traditions also include Kriya, Upa (called "Charya"), and Yoga, with the Anuttara yoga class substituting for Mahayoga and Atiyoga . </P>

Who wrote the main text associated with yoga