How Old is Yoga?

Yoga is believed to be 5000 or more years old knowledge that human beings have known and has used to keep themselves mentally, physically and emotional healthy. Yoga word is derived fron Sanskrit language (Ancient Indian language) which means "to unite or join" or simply union. 

Yoga could mean different things to different people coming from different background, country and culture. For someone yoga is philosophy, for others it is way of life, and for others it could be simply physical/mental exercise to stay healthy. Still for others it could be a way of rejuvenating your mind and body and get away from stress of day to day life and relax. Some may practice yoga in order to improve their memory and concentration. Yoga could a path that leads to achievement of different goals for different people. Yoga practitioner generally would be focused on particulat sect of yoga like Raja yoga, Hatha yoga, or Kriya yoga as learning, incorporating and teaching all of the yoga knowledge would be very challenging because of its vast nature of knowledge and practising methods which will need expectional amount of time and dedication to learn.

Yoga also have been referred to as being a science or technology of emancipation (freedom from cycle of birth and death)

Origination & Propogation of Yoga

Ancient Hindu books like Upanishad, Bhagavad Gita, Patanjali Yoga Sutras many others outlines and describes the criterias of learning and mastering various yoga asanas(postures) for healthly body and mind. Many western people have been visiting India to learn this ancient science of mind, body and spirit and propogate them in their own countries.

Many Indians have positively contributed towards this amazing science of yoga and meditation and have successfully taught them to millions of people in India, and abroad. Some of the prominent people that has helped yoga to become widely acceptable both inside and outside India are Maharishi Mahesh Yogi, Swami Ramdev, Swami Sivananda Saraswati, Swami Niranjananda Saraswati, Swami Satyananda Saraswati, Swami Vivekananda, Swami Prabhupada, Paramahansa Yogananda, Ramakrishna Paramahamsa, Swami Vishnu-devananda and many others. 

Four Branches of Yoga According to Bhagavad Gita

Bhagavad Gita is one of the oldest Hindu scripture that discusses about four major branches or parts of Yoga that can allow human beings to become one with God or in other words attain salvation. These four branches are 

1. Kriya yoga : Also known as Karma yoga which means acts or deeds. Kriya is sanskrit  word which means process. In nutshell Kriya yoga teaches and preaches how the good and bad action of living brings them closer to God or vice versa.
2. Bhakti yoga : Bhakti is a Sanskrit word which means devotion, and Bhakti yoga preaches and teaches about attaining salvation through devotion to deity.
3. Jnana yoga : Jnana is a Sanskrit word which means knowledge, and Jnana yoga teaches about attainment of salvation through seeking knowledge and pursuing God through intellectual endeavour.
4. Raja yoga : Raja is a Sanskrit word which means king and Raja yoga lays emphasis on attaining God or salvation through training the mind by doing mediation and doesn't deal intensly and directly with the physical body.

Yoga Sutras of  Patanjali
Patanjali was one of the first one who wrote and documented the yoga system in terms of sutras or aphorisms. Patanjali's 8 fold yoga system was written between 100BC and 200AD. There are total 196 yoga sutras written by sage Patanjali. The 8 fold yoga system includes

1. Yama (The five "abstentions"): violence, lying, theft, (illicit) sex, and possessions
2. Niyama (The five "observances"): purity, contentment, austerities, study, and surrender to god
3. Asana: Literally means "seat" or "postures" (In Patanjali's Sutras asanas refers to sitting postures used for meditation)
4. Pranayama ("Breath Control"): Control of prāna or vital life force
5. Pratyahara ("Abstraction"): Reversal of the sense organs
6. Dharana ("Concentration"): Concentrating by fixating the attention on a single object or idea.
7. Dhyana ("Meditation"): In depth contemplation on the truth or true nature of reality.
8. Samadhi ("Liberation"): Super-conscious state of enlightenment also known as state of eternal bliss.