Forehead Protector

A is a headband that is worn by almost every shinobi, composed of a metal plate engraved with the symbol of the ninja's Hidden Village, and normally a band of cloth which can be in different colours. The forehead protector is received once a ninja graduates from the Academy, and genin-level or higher ranked ninja are the only ones allowed to have and use them.

Background
The forehead protector is meant to symbolise pride in one's village, as well as a symbol of fealty. Ninja consider it an honourable, important part of their tradition, and make a point of wearing it at all times, especially when sparring with a comrade from the same village. For example, after the search for Tsunade, Naruto was disgusted by Sasuke's refusal to wear his forehead protector during their fight. There are also some ninjas who do not wear their forehead protectors, despite still being loyal to the village (such as the Sannin, Shizune, and Nagato). Some characters such as Shino Aburame still wear their forehead protectors under their clothing, keeping it from being visible being under his hood (in part II worn in the conventional style).

Variations
Despite the name "forehead protector", it can be worn in many different styles. For example, while the majority do wear theirs in the traditional manner, Sakura uses hers as a hair-band, Shikamaru has his on his upper left arm, whereas Ino (in Part I) wore hers as a belt, Rock Lee and Might Guy wear theirs as a belt when they wear their green jumpsuits, while Temari (in Part I) and Hinata wear theirs as chokers. Genma Shiranui wears his forehead protector like a bandanna with the village symbol facing backwards. Others such as Izumo Kamizuki and Chōji Akimichi (in Part I) wore theirs like customised bandanna. Tobirama Senju, Kisame Hoshigaki, Zaku Abumi and Yamato also wear a mask-style forehead protector that frames their faces, rather than a cloth wrapping around their heads. Kankurō wears his on his hood. Gaara wraps his on his sand gourd. Yagura uses a undershirt in which is the protector of Kirigakure in the middle and Chōjūrō uses it like a badge on his chest. Kakashi Hatake and Tonbo Tobitake wore theirs as makeshift eye-patches. Some characters even wear their headbands underneath their clothing; for example, Konan wears hers underneath her Akatsuki cloak on her right hip.

Several missing-nin such as Zabuza Momochi do not stop wearing their forehead protector, while others such as Orochimaru may discard them. Akatsuki members who do retain their forehead protectors carve a long, horizontal scratch across the symbol, to show they have rescinded their allegiances and rejected their villages. Also, while the citizens of Amegakure currently bear the same scratches across their forehead protectors, it does not mean they are missing-nin. Rather, it symbolises their victory over the civil war between Hanzō the recognised leader of Ame and Pain, the leader of Akatsuki rebel faction.

Jiraiya also wears a special forehead protector, which, instead of a piece of metal with the village's symbol attached to a cloth, it is a thick metal band, shaped like a frog's head, with the kanji on the centre. Forehead protectors date to the time of the Sage of the Six Paths and his children, the earliest one seen being worn by Asura. It was a regular headband with no symbol.

Since the formation of the Allied Shinobi Forces a new forehead protector has been crafted by Mifune, one with the kanji for on it. This symbolises that whereas once each ninja fought for their villages separately, they would now stand united under one banner for the same cause. The members of the Alliance wear this in place of their original forehead protector.

Colours and Styles
Throughout the course of the series the cloth of the ninja forehead protectors have been seen in many different colours and worn in many different styles.
 * Navy Blue: This is the most common colour of forehead protectors. Many ninja keep this colour for the entirety of their ninja career.
 * Crimson: Some ninja have a crimson-coloured forehead protectors such as Rock Lee and Might Guy. Other ninja changed from blue to crimson over the time-skip including Sakura Haruno and Chōji Akimichi. Iwagakure ninja also tend to use crimson coloured forehead protectors.
 * Black: Many ninja also wear black forehead protectors such as Kakashi Hatake, Sai, Itachi Uchiha, Neji Hyūga, Gaara, and Temari. Many ninja changed from blue to black over the time skip, including Naruto Uzumaki, Tenten, Iruka Umino, and all of Team Kurenai.
 * White: While hardly ever seen, forehead protectors can be pure white in colour such as Killer B and several other ninja from Kumogakure, and the Four Celestial Symbols Men. During a flashback from Chōji Akimichi, a Konohagakure ninja was seen wearing a white forehead protector
 * Purple: Several Otogakure ninja have been seen wearing purple forehead protectors, such as Zaku Abumi, Kin Tsuchi, and Dosu Kinuta. Inoichi Yamanaka also wears a purple forehead protector. Also, some shinobi from Hoshigakure wear forehead protectors, such as Akahoshi. Kinkaku and Ginkaku also wore purple forehead protectors.
 * Brown: A Kumokagure genin has been shown wearing a brown forehead protector in the ninth OVA.

Modified Forehead Protectors
There have been some cases where the design of the metal plate or cloth has been modified in some way aside from cloth colour.
 * The Demon Brothers, Gōzu and Meizu, have black metal horns attached to their forehead protectors. Gōzu has one horn, while Meizu has two. It is likely these helped them gain their nickname.
 * Jiraiya wore a horned forehead protector with the kanji for, which denotes his affiliation with Mount Myōboku.
 * Yamato and Tobirama Senju's forehead protectors are made in a way that covers their cheeks as well. This type is called happuri.
 * Some characters, most notably Zabuza Momochi and Naruto Uzumaki, have longer than normal cloth.
 * Yahiko and the Six Paths of Pain wore forehead protectors that weren't tied at the back of their heads, but were instead one piece of cloth. They could have possibly been held together with an elastic band.
 * Kisame Hoshigaki's forehead protector cloth seems to expand near as it goes around the back of his head and is one whole cloth.
 * Kakuzu's forehead protector cloth form a triangular shape in the front.
 * Ibiki Morino, Genma Shiranui, and Hayate Gekkō have bandanna-style forehead protectors.
 * Hiruzen Sarutobi's bandanna-style forehead protector wrapped around his helmet with extremely long ties, usually trailing behind him.

Trivia

 * On the cover for chapter 567, each jinchūriki is shown with a white forehead protector with the kanji for the number of tails of their respective tailed beasts.
 * Masashi Kishimoto, in an interview, noted that he created forehead protectors because he found it too cumbersome to draw Naruto's goggles every week.

Stirnband Bandeau frontal Pelindung Dahi Протектор