The eight limbs (Ashtanga) of Patanjali's Yoga Sutras
Yama (ethical restraints, including non-violence and truthfulness), Niyama (personal observances, including cleanliness and contentment), Asana (posture), Pranayama (breath control), Pratyahara (withdrawal of the senses), Dharana (concentration), Dhyana (meditation), and Samadhi (absorption or union — the traditional culmination of the path). Note: "Ashtanga" here refers to Patanjali's eight-limbed framework, distinct from the modern physical practice also called "Ashtanga Yoga," developed by K. Pattabhi Jois in the 20th century.
Major physical styles practiced today
Hatha Yoga broadly refers to physical-postural yoga generally, and specifically to a slower, foundational style emphasizing static poses and alignment; its classical text, the Hatha Yoga Pradipika, was compiled by Swami Svatmarama around the 15th century. Ashtanga (Vinyasa) Yoga, developed by K. Pattabhi Jois, links a fixed, physically demanding sequence of postures with synchronized breath. Iyengar Yoga, developed by B.K.S. Iyengar, emphasizes precise alignment, often using props such as blocks, straps, and bolsters. Other well-known styles — Kundalini, Yin, restorative, and power/vinyasa flow — vary in pace and intensity, from gentle and meditative to physically vigorous.
Pranayama — breath as practice
Pranayama (prana, "life force" + ayama, "extension/control") is the formal practice of regulating the breath, used both within postural yoga sessions and as a standalone practice. Common techniques include nadi shodhana (alternate-nostril breathing), kapalabhati (a forceful exhale technique), and ujjayi (a slight throat constriction producing an audible breath, commonly used throughout Ashtanga/Vinyasa practice).
Documented benefits
Research on yoga's physical practice reports evidence for improved flexibility, balance, and strength, and — similar to meditation — modest-to-moderate benefits for stress, anxiety, and lower-back pain across various studies. As with any exercise practice, benefits scale with consistency, and yoga is not a substitute for medical treatment of diagnosed conditions.
Getting started safely
Beginners are generally advised to start with a foundational style (Hatha or a beginner-labeled Vinyasa class), work with a qualified instructor who can correct alignment, and modify or skip poses that cause pain — distinct from the ordinary discomfort of a stretch — particularly for pre-existing joint, spine, or cardiovascular conditions, where a doctor's input is worth seeking first.