One of two types of yoga outlined in Patañjali's Yoga Sūtra (2.28–55; 3.1–8), and associated by some with Patañjali himself. The eight limbs are divided between ‘outer’ (bahir-aṅga) and ‘inner’ (antar-aṅga). The outer limbs are yama (restraint, ethics), niyama (self-discipline), āsana (posture), prāṇāyāma (control of the vital breath), and pratyāhāra (withdrawal of the senses). These are considered prerequisites for the more advanced inner limbs: dhāraṇā (concentration), dhyāna (meditation), and samādhi (absorbed concentration). See also kriyā-yoga.