Kakashi is the son of Sakumo Hatake, also known as the "White Fang of Konoha". His mother apparently died when he was young. Kakashi has been known since a young age as an extremely gifted prodigy, regarded by many as the best of his generation. He had received top marks and had shown an innate aptitude for the ninja arts while in the academy. This permitted him to graduate from it in a single year at the top of his class at the age of 5, and then becoming a chūnin a year later.
Despite his own success, his father fell into disgrace after choosing to save his comrades rather than complete an important mission, causing Konoha to suffer in the war effort. Dishonoured, Sakumo took his own life after a deep depression and a drop in his skills, which caused Kakashi to lead his life strictly by the ninja code.
Kakashi was teamed with Obito Uchiha and Rin under the leadership of Minato Namikaze. At the age of 13, soon after becoming a jōnin, Kakashi was assigned to lead Obito and Rin on a mission that would benefit Konoha in the ongoing Third Shinobi World War. They were to destroy the Kannabi Bridge, which was being used by Iwagakure forces to move into Kusagakure. This would also be Konoha's first huge offensive move in the war. On their way to the bridge, Rin was kidnapped by two Iwagakure ninja named Kakkō and Taiseki. Obito immediately suggested that they rescue her, but Kakashi disagreed on the basis that they needed to complete their mission, opting not to make the same mistake his father did.
Kakashi arrived in time to save Obito from Taiseki, using his father's blade to combat him. Despite the 2-to-1 disadvantage, Taiseki was able to attack and damage Kakashi's left eye, who took the blow that was intended for Obito, giving him a permanent scar.
oon after the end of the war, when the Nine-Tails attacked Konohagakure, Kakashi and the rest of his peers were barred from participating in the defence of the village by Kurenai's father and other older shinobi.
Over the years, Kakashi became well-known among all the Five Great Shinobi Countries for the extensive use of his Sharingan, gaining him a reputation as "the man who has copied over a thousand techniques", hence his nickname. Kakashi eventually joined the Konoha ANBU.
He later left for unknown reasons, but maintained strong connections with the ANBU. Kakashi eventually became a team leader, and tested many genin. As the Third Hokage told Iruka, Kakashi had never passed any of them due to their inability to live up to his expectations of working as a team.
In the anime, he once had a mission where one of his team-mates, Iruka Umino, was injured, paving the way for the latter to become an instructor at the Academy. When Iruka was having doubts at being assigned to be the homeroom teacher of Naruto Uzumaki, Kakashi served to remind him of his real reasons for wanting the post in the first place.
Appearance
Kakashi has always been seen with the standard Konoha shinobi outfit along with iron plated gloves from his ANBU days. During the Kakashi Gaiden, he is seen with a black T-shirt with white stripes in the middle of the sleeves. On his arms he wears black sleeves (which he presumably cut out from his shirt) with metal arm protectors over them. He also has leather straps around his back and chest, and his family's White Light Chakra Sabre is kept in a small holder out in the back. He also wore pants similar to the ones he wears today. He appears to wear the same type of outfit as a child (as seen in a flashback). However, in another flashback he is shown wearing a sleeveless black shirt similar to one he sometimes wears as an adult. This type of shirt is presumably for casual wear.Kakashi's personality is further emphasised by his generally lazy expression, aloof manner, relaxed voice, and minimalist attitude. In serious situations, however, he is shown to have a very stern and intense look. The cover page for chapter 16 also shows him wearing a chain necklace. Another noticeable feature to Kakashi, other than his unique left eye, is the thin scar running over it and down to his cheek. He is a tall, fit ninja, is characterised by his tall and spiky white hair, forehead protector regularly covering his scarred left eye, and his chronically visible mask. He was once mistaken by Chiyo for his father Sakumo Hatake, who he is considered to greatly resemble.
While it has yet to be revealed why, he has, since a young age, always been seen concealing the lower half of his face. What he looks like remains a point of interest for his students, who try to find out what he looks like in various omake specials in the series. Episode 101 is devoted to Team 7 trying to remove their sensei's mask, and suggests that he is in fact very handsome, as seen from Teuchi and Ayame's reaction to seeing his face. In the few instances that he is seen without his mask, it has been seen that he has a narrow jaw-line; in these instances the parts of his face normally covered by his mask are obstructed from view.
Abilities
Kakashi is a natural genius, evidenced by the speed he rose through the ninja ranks; he graduated from the Academy at age 5, becoming a chūnin at age 6, a jōnin at 13, and had a long tenure as an ANBU. During his career he has amassed a technique arsenal of over a thousand different techniques, making him Konoha's expert in the field. His various accomplishments have earned him much praise by his fellow Konoha ninja and he holds a position of great influence. He is frequently given responsibility for important tasks, such as watching Naruto in case the seal of the Nine-Tailed Demon Fox begins to fail and being considered for Hokage.Other ninja villages are very aware of Kakashi's abilities and, upon meeting him in battle, either fear for their safety or grow excited by the challenge Kakashi is sure to pose. Pain was so concerned by Kakashi's abilities that he tried to kill him for fear that he would someday interfere with Akatsuki's plans.
Intelligence
By the age of 13, Kakashi had enough experience on the battlefield to detect a hiding enemy's presence, impressing his sensei, Minato.His long career as a jōnin, and formerly as an ANBU, have only expanded his knowledge, allowing him to handle virtually any situation (though, by his own admission, he does not believe he is suitable for the Hokage position). For these reasons Kakashi has been assigned to a variety of teams - typically as a leader - and he is always able to work well with his team-mates. Chōza Akimichi attributes Kakashi's success to his approach to battles: he avoids direct combat by using misdirection and clones until he can determine the opponent's skills, at which point he modifies his tactics to fit the situation. He is aided in this regard by his calm personality, which allows him to analyse a given situation with some detachment. He is, however, capable of "going wild" when upset, at which point he relies on his allies more than usual to make up for his heightened emotions.Kakashi has also shown repeatedly to be a highly capable teacher. He has come up with various unorthodox methods to help his students produce impressive leaps in their abilities in weeks what would normally take months if not years of intense training.
Sharingan 
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Added by TheUltimate3Kakashi has somehow been able to improve his Sharingan with time. When he first received the Sharingan it had only two tomoe, but by the start of the series it has progressed to three. In addition, by Part II, Kakashi has extended the amount of time he can sustain using the Sharingan, as he is seen using it for seemingly a day while testing Naruto and Sakura.
Mangekyō Sharingan
During the time skip, Kakashi further improved his Sharingan by developing his own Mangekyō Sharingan through undisclosed means. With it he can perform Kamui, a technique that sucks everything within a small area to another dimension. When he is first seen using Kamui he lacks proper control, leaving him prone to either hitting targets he was not aiming for or missing completely. He improved his skill with Kamui by the invasion of Pain, seen when he successfully sends fast-moving projectiles to another dimension with it. Kamui's chakra requirements are even greater than those of the standard Sharingan, such that he has to be hospitalised for a week after using it three times in one day. Despite Kamui being his only known Mangekyō Sharingan technique, he is familiar with Tsukuyomi, Amaterasu, and Susanoo. He is also aware of the risk the Mangekyō Sharingan poses to the user's eyesight, though he has never shown signs of deteriorating vision
