Terminology
The word asana in Sanskrit does appear in many contexts denoting a static physical position, although traditional usage is specific to the practice of yoga. Traditional usage defines asana as both singular and plural. In English, plural for asana is defined as asanas. In addition, English usage within the context of yoga practice sometimes specifies yogasana or yoga asana, particularly with regard to the system of the Ashtanga Vinyasa Yoga. That said, yogasana is also the name of a particular posture that is not specifically associated with the Vinyasa system, and that while "ashtanga" (small 'a') refers to the eight limbs of Yoga delineated below, Ashtanga (capital 'A') refers to the specific system of Yoga developed by Sri Krishnamacharya at the Mysore Palace.
Yoga first originated in India. In the Yoga Sutras, Patanjali describes asana as the third of the eight limbs of classical, or Raja Yoga. Asanas are the physical movements of yoga practice and, in combination with pranayama or breathing techniques constitute the style of yoga referred to as Hatha Yoga. In the Yoga Sutra, Patanjali describes asana as a "firm, comfortable posture", referring specifically to the seated posture, most basic of all the asanas. He further suggests that meditation is the path to samādhi; transpersonal self-realization.
The eight limbs are, in order, the yamas (restrictions), niyamas (observances), asanas (postures), pranayama (breath work), pratyahara (sense withdrawal or non-attachment), dharana (concentration), dhyana (meditation), and samadhi (realization of the true Self or Atman, and unity with Brahman (The Hindu Concept of God)).
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