Copy Ninja Kakashi

Kakashi is the Konohagakure Jōnin assigned in the beginning of the manga and anime to train and look after Team 7, including Uzumaki Naruto, Uchiha Sasuke, and Haruno Sakura. He is also known as Copy Ninja Kakashi or (写輪眼のカカシ, Sharingan no Kakashi), Kakashi the Sharingan User.

These aliases refer to the fact he copied more than a thousand jutsu (ninja techniques) using his left eye, which possesses the Sharingan, an advanced bloodline trait found only in some members of the nearly defunct Uchiha clan. The three comma-like marks aligned in a wheel in the pupil of his left Sharingan-activated eye indicate that it is fully developed for a normal Sharingan, with only one more level -- Mangekyō Sharingan. However, he is not a real Uchiha, and in fact receives the Sharingan eye from a dying Uchiha Obito, his teammate, during his first mission as a jōnin. During that mission, Kakashi injured his left eye in a battle trying to protect Obito, leaving behind the scar (which has nothing to do with the transplant operation). The scar comes from a slash that destroyed his original eye.