Yoga a generic term for a physical, mental, and spiritual discipline originating in ancient India and found in Hinduism, Buddhism, Jainism and Sikhism. Specifically, Yoga is one of the six orthodox schools in Hindu philosophy. It is based on the Yoga Sutras of Patanjali and aims to use meditation to attain spiritual insight and tranquility. The Sanskrit word yoga has the literal meaning of "yoke", from a root yuj meaning 'to join', 'to unite', or 'to attach'. As a term for a system of abstract meditation or mental abstraction it was introduced by Patanjali in the 2nd century BC. Someone who practices yoga or follows the yoga philosophy with a high level of commitment is called a yogi or yogini.
Hatha Yoga is the physical science of balancing the opposite energies in the body. The word Hatha is composed of two syllables, namely HA and THA. HA refers to the solar / masculine / positive energy and THA to the lunar/feminine/negative energy and Yoga meaning 'union'. Asanas Pranayamas, Kriyas, Surya Namaskar, Mudras and Bandhas are included in Hatha Yoga.
Asana is a pose or posture used in the practice of yoga. Asana brings steadiness, health and lightness of body. A steady and pleasant posture produces mental equilibrium and prevents fickleness of mind. By practicing them one develops agility, balance, endurance and great vitality.
Pranayama is the art of breath control. Pranayama essentially involves three things: regulating the breath, controlling the vital force and chanalizing the Pranas in the right directions.
Kriyas are cleansing exercises to remove toxins from the body. There are six kriyas: Neti (nasal cleansing), Nauli (abdominal churning), Dhauti (upper digestive tract cleansing), Basti (colon cleansing), Kapalabhati (lung and bronchial tube cleansing) and Trataka (steady gazing).
Meditationis an act of reflection and observation to convey the serenity and sense of detachment that can be experienced when the body is relaxed, the restless mind is at peace and one enjoys a blissful state.
Four different paths of Yoga
Yoga of Knowledge (Veda, Upanishada, Shankara).
Yoga of Devotion (Puranas ).
Yoga of action (Bhagavad Gita ) which teaches to balance our actions and learn acceptance.
Classical Yoga (Patanjali Yoga sutras) deals with our mind realising the Self or God through meditation and associated practices.