Prana (prāṇa) is the Sanskrit word for "life force" or vital principle. In yoga, Indian medicine, and martial arts, the term refers to a cosmic energy believed to come from the sun and connecting the elements of the universe. The universal principle of energy or force, responsible for the body's life, heat and maintenance, prana is the sum total of all energy that is manifest in the universe. This life energy, prana, has been vividly invoked and described in Vedas. In Ayurveda, tantra and Tibetan medicine "praṇā vāyu" is the basic vāyu (wind, air) from which all the other vāyus arise. It is analogous to qi.
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