PRAYANAM The elixir of Life.

The greatest gift of God after giving us life is the involuntary process of breathing, for if it was voluntary then maybe humans would have forgotten it, which would have been fatal. It would also be not possible for the living beings to sleep as all the voluntary control ceases during sleep.
As is evident, all living beings can survive without food or water for a few days, but it is impossible to survive without air even for few minutes. Thus breathing is the most important function for all living beings. The ancient system of Yoga therefore lays great stress on right breathing techniques. The Pranayama is voluntarily or consciously controlling the breathing process. The great sage Patanjali minutely studied the breathing process and developed an art of controlled breathing Pranayama.
Breathing constitutes, inhalation, retention, and exhalation. By bringing about variations in inhalation i.e. either through right nostril, left nostril or both, exhalation through right nostril, left nostril, or both, internal or external retention of breath, altering the duration of inhalation or exhalation or both, there are sixty four different types of Pranayams.
Prana (the air we breathe) is a life force or energy that keeps one going. When one breathes in he takes in this all pervading energy, during retention one savours this energy and while exhaling one dispels out the toxins out of the body. Thus practice of Pranayama helps in absorbing the energy and cleansing our body of the toxins.
An average person normally inhales about 500cubic centimeters of air, and during deep inhalation takes in as much as six times i.e. 3000 cubic centimeters of air. Generally a person uses his faculty of breathing from about 50% to 70% only. Pranayama helps in increasing the lung capacity and achieve optimum ventilation to optimize the faculty of breathing. The normal rate of breathing is about 15 breaths per minute i.e. about 21600 breaths per day. According to the ancient scriptures (Vedas) the lifespan is not measured by years but by the number of breaths. Pranayama lengthens the duration of breath bringing it down to about 6-8 breaths per minute, thus promoting longevity.
Another major benefit of Pranayama is that it calms the mind which facilitates clear thinking and helps in developing strong will power. Pranayama permeates energy not only in the gross body but also the subtle and the astral body, thus assisting in spiritual development and release of the divine cosmic energy Kundalini situated at the base of the spine. Mastering of pranayama along with meditation leads one to attain self-bliss and live a wholesome life.