Tai chi, properly taijiquan, "supreme ultimate fist", is a Chinese internal martial art practised today by millions worldwide as a slow, flowing exercise for health, balance and meditative calm. Its practitioners move through a continuous sequence, or "form," of postures performed with deliberate slowness, the whole body coordinated, the weight shifting smoothly from one leg to the other, the breath and attention gathered. Though most who practise it seek its benefits to health and serenity, tai chi is at root a martial art, its every movement carrying a combat application, and it belongs to the family of "internal" arts that cultivate the body's inner energy, qi, rather than relying primarily on muscular force.
Its name and philosophy draw on the taiji, the "supreme ultimate" of Chinese cosmology, the interplay of yin and yang whose alternation generates all things. The form is understood as an embodiment of this interplay, the constant exchange of empty and full, yielding and advancing, stillness and motion, so that the practitioner rehearses in the body the principles the tradition finds at the root of the cosmos.