Vata is one of the three doshas, the fundamental humours of Ayurveda, the traditional medicine of the Indian subcontinent. In its classical composition Vata is formed of the elements air and ether (akasha), and it is the principle of movement, governing breath, circulation, the nervous impulses, and all motion within the body. When balanced it gives vitality, quickness, and creativity; when disturbed it is associated in the tradition with dryness, cold, anxiety, and irregular function. Each person is held to have a constitution (prakriti) in which the three doshas combine in a characteristic proportion, and Ayurvedic diagnosis and treatment aim at keeping them in balance through diet, regimen, and season.
Classical Ayurvedic literature further divides Vata into five subtypes, each seated in a different region and governing a different function: prana vata, in the head and chest, governing breath and swallowing; udana vata, in the throat and chest, governing speech and effort; samana vata, at the digestive fire, aiding the breakdown of food; vyana vata, pervading the whole body, driving circulation and the reflexes; and apana vata, seated in the pelvis, governing elimination, menstruation and childbirth. The theory appears in both of the two great classical compendia, the internal-medicine focused Caraka Samhita and the surgically focused Susruta Samhita, and its presence in both, texts with different practical concerns, reflects how central the tridosha framework is held to be across the whole of classical Ayurvedic literature. These are the concepts of the Ayurvedic tradition, a living system of medicine, presented here as that tradition frames them.