According to the yogis, the whole universe(creation) is composed of two materials, Akasha (open space, ether) and Prana. Akasha is the omnipresent, all penetrating existence. Everything that has form, everything that is the result of compounds, is evolved out of this Akasha. It is the Akasha that becomes the air, that becomes the liquids, that becomes the solids; it is the Akasha that becomes the plants, every form that we see, everything that can be sensed, everything that exists. It itself it cannot be perceived; it is so subtle that it is beyond all ordinary perception; it can only be seen when it has become gross, has taken form. At the beginning of creation there is only this Akasha; at the end of the cycle, the solids, the liquids, and the gases all melt into the Akasha again, and the next creation similarly proceeds out of this Akasha.
By what power is this Akasha manifested into this? —By the power of Prana.
Just as Akasha is the infinite omnipresent material of this universe, so is this Prana the infinite, omnipresent manifesting power of this universe. At the beginning and at the end of a cycle everything becomes Akasha, and all the forces that are in the universe resolve back into the Prana; in the next cycle, out of this Prana is evolved everything that we call energy, everything that we call force. It is the Prana that is manifesting as motion; it is the Prana that is manifesting as gravitation, as magnetism. It is the Prana that is manifesting as the actions of the body, as the nerve currents, as thought force. From thought, down to the lowest physical force, everything is but the manifestation of Prana. The sum-total of all force in the universe, mental or physical, when resolved back into its original state, is called Prana. “When there was neither aught nor naught, when darkness was covering darkness, what existed then? That Akasha existed without motion.” The physical motion of the Prana was stopped, but it existed all the same. All the energies that are now displayed in the universe we know, by modern science, are unchangeable. The sum-total of the energies in the universe remains the same throughout, only, at the end of a cycle, these energies quiet down, become potential, and, at the beginning of the next cycle, they start up, strike upon the Akasha, and out of the Akasha evolve into various forms, and, as the Akasha changes, this Prana changes also into all these manifestations of energy.
The question is raised in the Vedas, “What is that, knowing which we shall know everything?” Thus, all books, and all philosophies that have been written, have been only to prove That by knowing which everything is known. If a man wants to know this universe bit by bit he must know every individual grain of sand, and that means infinite time for him; he cannot know all of them.
Then how can knowledge be? How is it possible for a man to be all-knowing through particulars? The yogis say that behind this particular manifestation there is a generalization. Behind all particular ideas stands a generalised, an abstract principle; grasp it, and you have grasped everything.
Just as this whole universe has been generalized, in the Vedas, into that One Absolute Existence ( Atman/Brahman). He who has grasped that existence has grasped the whole universe. So all forces have been generalized into this Prana, and he who has grasped the Prana has grasped all the forces of the universe, mental or physical. He who has controlled the Prana has controlled his own mind, and all the minds that exist. He who has controlled the Prana has controlled his body, and all the bodies that exist, because the Prana is the generalised manifestation of force.
We see sects in every country who have attempted this control of Prana , there are Mind-healers, Faith-healers, Spiritualists, Christian Scientists, Hypnotists, etc., and if we analyse these different groups we shall find that the background of each is this control of the Prana, whether they know it or not. If you boil all their theories down the residuum will be the same. It is the one and same force they are manipulating, only unknowingly. They have stumbled on the discovery of a force, and do not know its nature, but they are unconsciously using the same powers which the Yogi uses consciously , and which come from Prana.
GENERAL CONCEPT OF PRANIC BODY
The meaning of prana is ‘life force’ or ‘vital energy’. In the universal sense, prana is responsible for all creation. It is the prana within every created object, whether a planet, an asteroid, a blade of grass or a tree, that gives it existence, material form. If there were no prana within that object or manifestation there would be no form; it would gradually crumble and go out of existence. So, on the macrocosmic level, prana is like a vast, all encompassing sea of vital energy. Every object in creation is floating in that sea like a fish in water, and from that sea of energy we gain everything we need for life. That prana is known as cosmic prana or mahaprana.
From mahaprana each individual gains his personal existence. The quantum of prana which gives life to the individual is called individual prana. We separate it from mahaprana, but it is the same prana. If you fill a jar with water and place it in a lake or pond, the water inside the jar is the same as the water outside. We think of ourselves as separate entities or beings moving around in this world, but we are all part and parcel of the universal or cosmic prana. This cosmic prana or energy has been eulogized in all the ancient cultures and religions, and known as mahashakti, mahakundalini, mahamaya, the great mother. Through that mother we can connect ourselves to the highest reality or pure consciousness ( known as shiva)
It is said from pure consciousness emanated pure energy or mahaprana. Pure consciousness and pure energy exist in the unmanifest dimension. However pure consciousness become manifest through pure energy. So from pure prana emanated the first manifestation in creation which is sound. Sound is the most subtle aspect of manifest prana. Form gradually emanated from sound and from the subtlest form came all the objects of creation, including our own individual being. So all of us have our life within this concept of cosmic prana. Our real mother, our true mother, is mahaprana or mahashakti.
THE FIVE PRANAS
The prana within our individual being has been categorized into five groups, but we need to understand that the individual prana is one prana. We do not call it mahaprana, but we refer to this overall prana which gives us life as Prana. When Prana leaves the body then we will be clinically dead and gradually our form will disintegrate.
To understand the functions of individual prana we divide it into five main categories: Prana, samana, apana, udana and vyana. These are the five pranas which together maintain the entire function of our physical form.
Prana: Individual Prana is located between the diaphragm and the throat. This prana is an upward flowing force. It maintains the function of the lungs and heart, and is responsible for inhalation and exhalation, and for the swallowing and regurgitation of food. Although it is an upward moving force in general, it also has the ability to move downward in that region.
Samana: The next prana is known as samana. The word sam means ‘equal’ or ‘same’. Samana is located between the diaphragm and the navel. Although it is a small area physically, it is very important. Samana is responsible for the digestive energy and coordinates and motivates the digestive organs such as the stomach, liver, pancreas and large intestine. If anything goes wrong with your samana energy then you will become weak and thin because you will not be able to absorb the nutrients in the food properly. It takes a tremendous amount of energy to digest, burn and separate the nutrients which we take in daily. That is one of the greatest pranic expenditures within our body.
Apana: The third prana is apana. Apana is located between the navel and the perineum in the pelvic region. It is a very important energy field which is responsible for sexual activity, procreation, production of semen and ovum, elimination of urine, faeces, gas, wind and expulsion of the foetus. This energy is mainly downward flowing, but we can also redirect it upward to the brain.
Udana: The fourth prana is udana. Udana is located in the head region as well as the limbs, between the shoulders and the fingertips, and from the hips down to the toes. It is associated with the motor and sensory nervous system. Udana controls an immense amount of energy. It coordinates and activates the nervous system, moves the limbs of the body and receives and categorizes the different sensory inputs from the external world. Udana is connected intimately with the functions of the five senses, eyes, nose, mouth, ears and touch. If this prana becomes weak or disturbed, we find it difficult to coordinate, balance and integrate our sensory and motor nerves.
Vyana: The fifth prana is vyana. Vyana is an integral prana. It exists throughout the body as an underlying reserve force, so if anything goes wrong in another area of prana, vyana can step in and support that weak or imbalanced area. Thereby vyana prevents diseases and imbalances from occurring in the different systems and parts of the body. Should vyana become weak or deficient then diseases will arise because there will be no backup system.
Ref :- 1)Raja yoga – Swami Vivekananda
2) Prana and Pranayama – swami Niranjanananada saraswati