Bending is the ability to manipulate an element and is significant to many aspects of life in the Xuiz and Yuiz Universes. There are five known bending arts; four of them bend a specific physical element while the fifth bends the energy within the human body itself, it is in fact, a form of Kinesis abilities. The four elemental bending arts are based on the four classical elements, water, earth, fire, and air, and each is manipulated through certain martial art styles which are reminiscent of the qualities of the element itself. While bending is traditionally performed through the motions of one's hands and feet, certain benders are able to effectively manipulate their element with only minimal movement of their body, such as by using just their head or torso. In even rarer cases, benders are able to perform their bending without the aid of any physical movement at all, by instead using sheer focus and force of will, a skill known as psychic bending. Each element is also associated with a particular nation in the world; the Water Tribe corresponds with waterbending, the Earth Kingdom with earthbending, the Fire Nation with firebending, and the Air Nomads with airbending. However, other bending affiliated groups exist, like the Foggy Swamp Tribe for waterbending and the Sun Warriors for firebending.
The fifth bending art, energybending, is unlike the other four in that little physical action is required to direct the bending itself. The four elemental bending arts are all dependent on the energy, or chi, within the human body, relying on its flow through the body to manipulate a specific element. A person is able to bend when they extend the influence of their chi beyond the body to interact with the environment. Energybending, on the other hand, is concerned with the manipulation of the energy itself and is able to remove or grant bending abilities.
Though each nation is affiliated to a specific bending art, not all citizens from any nation, with the exception of the Air Nomads, are born with the ability to bend an element. In the case of mixed marriages, the children may be benders of either element if they are benders at all; for example, firebender Mako and earthbender Bolin are brothers with parents from the Fire Nation and the Earth Kingdom. The only case of any one person being able to bend multiple elements is the Avatar, who has the ability to practice all five bending arts.