Yoga was founded by Patanjali. The Yoga Sutra of Patanjali is the sure authority for the entire Yoga-darshan. Patanjali defines yoga as having 8 parts (astha-anga), and he defines the goal of these 8 steps of yoga as “ishvara pran-nidhan.” This means to give (nidhan) oneself, ones heart and life (prana), to the Personality of Godhead (ishvara). There is no other ultimate goal of yoga, though each stage has its own goals, and even each subpart has its own subgoals.
The stages are:
1) Yama – Rules.
This means controlling how you interact with others and with the world. The foremost rule is ahimsha, nonviolence. The foremost compoent of ahimsa is vegetarianism.
Ahimasa-siddhi, the perfection of ahimsa, results in it being literally impossible for anyone to be angry or violent in ones presence.
2) Niyama – Regulations
This means controlling how you treat yourself. How much you eat, how much you sleep, how much you have sex, etc. etc. etc. Celibacy is the primary niyama. The effect is that the nervous system and brain becomes supercharged and highly alert.
3) Asana – Posture
The third step is posture. These cause the body to be fully healthy. It is not really the goal that this makes us “fully aware and present” – rather the effect of perfecting asana is that there is no discomfort or disease at all in the body. A weak or sore body distracts the mind. Therefore yoga establishes health before establishing meditation.
4) Paranyama – breath
As asana makes the muscles and systems of the body free from pain and disease, ruling the breath (pranayama) cleans the mind and emotions of discomfort and mental disease.
5) Pratyahara – Withdrawl
When one is good in how he relates to others, to himself, and when ones body and mind are sound and present no distractions one can begin meditation. Meditation begins by withdrawing all ones awareness from the external world.
6) Dharana – Focus
Once the senses are withdrawn from external perception they can begin to sense the internal world. At this step one begins to focus on the ishvara (godhead) known as Parambrahma, Paramatma – who is the soul within the inner core of our own inner core.
7) Dhyana – Meditation
When that focus on the supersoul is undisturbed be attain the 7th stage of yoga.
8) Samadhi – Constant contemplation
When our focus on the supersoul NEVER ENDS, we attain perfection through yoga. This is the goal of yoga.