Ashtanga yoga (Sanskrit: अष्टाङ्गयोग, romanized: aṣṭāṅgayoga, "the eight limbs of yoga") is Patanjali's classification of classical yoga, as set out in his Yoga Sutras. He defined the eight limbs as yamas (abstinences), niyama (observances), asana (postures), pranayama (breathing), pratyahara (withdrawal), dharana (concentration), dhyana (meditation) and samadhi (absorption).