写輪眼 (Sharingan) is a special eye technique from the popular anime and manga series Naruto. It is a unique ability possessed by members of the Uchiha clan, allowing them to perceive fast movements, copy techniques, and see through illusions. The Sharingan evolves through emotional experiences, gaining more powerful forms with each evolution. The Sharingan has several abilities, including Genjutsu, which can manipulate an opponent's perception, and Tsukuyomi, a powerful illusion technique. Users can also predict movements in battle, making them formidable opponents. The Sharingan is a central element in the story, influencing many characters and their relationships.