In the world that "Avatar: The Last Airbender" shows, there is always only one person alive who can bend all four elements. That person is called the "Avatar." When one Avatar dies, he or she is reincarnated, or born again in another body. The Avatar's next body always belongs to the next nation in the Avatar Cycle. The cycle always goes in this order: water, earth, fire, air. Then it starts over again with water. The Avatar must learn how to bend the elements in the same order. He or she begins by learning how to bend the element of the country where they were born. Then he or she learns the next three elements in order. Usually, it is a challenge for the Avatar to learn how to bend the element that is the opposite of their first, or "native," element. For instance, the main character of the show, Aang, was born to Air Nomads, so air was the first element he learned to bend. The "opposite" element to air is earth, so for Aang, it was difficult to learn earthbending. This is because Earthbending focuses on steadiness and facing your opponent directly. This is different from airbending, which focuses on getting to your opponents in many different ways and changing your style quickly if it is necessary.