The whole system of Yoga is built on three main structures: exercise, breathing, and meditation. The exercises of Yoga are designed to put pressure on the glandular systems of the body, thereby increasing its efficiency and total health. The body is looked upon as the primary instrument that enables us to work and evolve in the world, and so a Yoga student treats it with great care and respect. Breathing techniques are based on the concept that breath is the source of life in the body. The Yoga student gently increases breath control to improve the health and function of both body and mind. These two systems of exercise and breathing then prepare the body and mind for meditation, and the student finds an easy approach to a quiet mind that allows silence and healing from everyday stress.

An Introduction to the techniques of Meditation

Meditation is an experience that cannot be described, just as colors cannot be described to a blind man. All ordinary experience is limited by Time, Space and Causation. Our normal awareness and understanding do not transcend these bounds.
Finite experience, which is measured in terms of past, present and future, cannot be transcendental. Concepts of time are illusory, for they have no permanence. The present, immeasurably small and fleeting, cannot be grasped. Past and future are non-existent in the present. We live in illusion.

The meditative state transcends all such limitations. In it there is neither past nor future, but only the consciousness of "I am" in the eternal NOW. It is only possible when all mental modifications are stilled.
The closest analogous state that we can experience is deep sleep, in which there is neither time, nor space, nor causation. Meditation, however, differs from deep sleep, for it works profound changes in the psyche. By curbing and stilling the oscillations of the mind, meditation brings mental peace.

On the physical level, meditation helps to prolong the body's anabolic process of growth and repair, and to reduce the catabolic or decaying process. Ordinarily the anabolic process predominates until the age of 18. From 18 to 35 there is balance between the two, and after 35 the catabolic process dominates. Meditation can significantly reduce the catabolic decline. This is because of the innate receptivity of the body cells.
Each of our body cells is governed by the instinctive subconscious mind. They have both an individual and a collective conciousness. When the thoughts and desires pour into the body, the cells are activated; the body always obeys the group demand. It has been scientifically proven that positive thoughts bring positive result to cells. As meditation brings about a prolonged positive state of mind, it rejuvenates body cells and retards decay.

One cannot learn to meditate, anymore than one can learn to sleep. one falls into both states. There are certain points to remember regarding the techniques and stages of meditation.