Ninja Ranks are variations from village to village, the general organisational structure and hierarchy of the ninja systems of each village is about the same. At the top of the organization is the Village Leader, or the Kage in the case of the Five Ninja Villages. They rule the village and its shinobi together with a council, usually consisting of highly ranked ninja and elders.
The actual shinobi forces are divided in three groups. The regular forces, the ANBU, and the Medical Teams.
The Regular Forces (known as Seiki Butai) form the foundation of the village and its shinobi system. The majority of the ninja are a part of these forces and together, either individually or in teams, they perform the majority of the missions the village receives. They are also tasked with the various duties within the organization, such as training and office work.
When an Academy Student graduates, they usually become a part of these forces, assuming the rank of Genin. Via various exams and tests, they can be promoted to higher ranks, first to Chunin then after that to Jonin and after that to Arunin. Sometimes, when a shinobi is specialized in a very specific skill, they can assume the rank of Special Jonin, which is ranked between chūnin and jōnin.
Academy Students (known as Akademi-sei) make up the student body of the Academy, where they are trained and prepared for life as a shinobi. They are not an actual part of the shinobi force, as they are still in the process of mastering the very basics of the ninja lifestyle. However, they can be conscripted as part of the war potential in times of emergency.
Genin (Literally meaning "Low Ninja", Meaning (Viz) "Junior Ninja") are the lowest level of ninja and also the ones that display the most difference in power. When they become genin, ninja start to do their bit for their village's economy – being sent on missions that the village gets paid for. They are typically sent either on D-Rank missions, which are almost entirely risk-free jobs of manual labour, or, rarely, on C-Rank missions, which are a cut above that and begin to verge on real "ninja" work that have a very low possibility of risk to the ninja involved. When Konohagakure was short-handed on upper-level ninja because of the invasion, the village had to occasionally send genin on higher-ranked missions.
Chunin (Literally meaning "Middle Ninja", Meaning (Viz) "Journeyman Ninja") are ninja who are qualified to guide other ninja and lead missions. Chunin have reached a level of maturity and ability that primarily consists of leadership skills and tactical prowess. Genin who do not have the skills to become chūnin are weeded out in the Chunin Exams. Some of them, like Iruka Umino and Daikoku Funeno move on to function as Academy teachers and others, like Shikamaru Nara, serve as team leaders in charge of small teams who need to make decisions and utilize the skills of the shinobi under their command to the maximum effect. Chūnin are typically sent on C-Rank or B-Rank missions.
Special Jonin (Tokubetsu Jonin; Literally meaning "Special High Ninja") are ninja who, rather than all-around Jonin training, have jōnin-level ability in a specific area or skill, much like warrant officers in real-world militaries. They are elite specialists in their areas and are often assigned as subordinates to regular jōnin when their services are needed.
Jonin (Literally meaning "High Ninja", Meaning (Viz) "Elite Ninja") are generally highly-experienced shinobi with great individual skill who serve as military captains. They are often sent on A-Rank missions, and experienced jonin may even be sent on S-Rank missions (which are considered to be the greatest difficulty).
Special Ranks and Functions
Besides the standard ranks of genin, chūnin, tokubetsu jōnin, and jōnin, there are some shinobi who bear a special rank or function.
Arunin ( Meaning "Ultimate Ninja" Viz Meaning "Strongest Ninja") are a new rank generally experienced shinobi invented by Tsunaku Senju after the first Grand Battle Royale was over, this rank is between Jonin and Kage.
A Kage (Literally meaning "Shadow") is the leader of one of the five most powerful Hidden Villages and generally are also the most powerful ninja in their respective villages. They are collectively known as the Five Kage (五影, Gokage; Literally meaning "Five Shadows").
Squads are a group of ninjas with a squad leader. Although the higher-ranking members of the regular forces often perform missions alone, most are done in teams. The most basic team is the one a genin is placed in after graduation. This so-called three-man squad consists of three genin under the guidance of a jōnin. These teams are meant to give the new shinobi practical skills, while already being a productive member of the organisation. Usually, strong bonds are cultivated between the members of such a team, lasting their entire lives. Because of these bonds and the fact that working with one's long-time team-mates is usually more efficient, these teams often last even after all members have been promoted to chunin or higher.
Besides these basic teams, there are also teams, and groups created for specific missions and tasks. Sometimes these are ad hoc teams only exist for the duration of the mission, such as the Sasuke Retrieval Team, but in certain cases these teams are more organised and lasting, such as the Twenty Platoons, created to battle the Akatsuki threat.
The ANBU (English TV "ANBU Black Ops"; Literally meaning "Dark Side"), short for Ansatsu Senjutsu Tokushu Butai (Literally meaning "Special Assassination and Tactical Squad"), take orders directly from the Kage, performing special high-level missions, such as assassinations and torture. The ANBU usually work in teams formed to the requirements of the mission, ensuring maximum success. The shinobi in the ANBU are hand-picked by the Kage; chosen for their individual capabilities and special skills. Age, gender, background, or previous rank bear no weight in this decision. Members can also leave the organization, as Kakashi did for unknown reasons to return being a Jonin, but he retained strong ties with the ANBU. They wear their mask even in their own village, for their identity as an ANBU agent is to be known only by the Kage and village elders, with the exception of Konohagakure's "Foundation" ANBU members who, unless ordered to, will otherwise only act on Danzo Shimura's orders.
There are apparently no true ranks within the ANBU, unlike within the regular forces. Team leadership and hierarchy seem to be based on merit and experience. The leaders of the teams are called squad leaders (Buntaichō), a position held in high regards.
There are various groups within the ANBU, aimed at various different functions and tasks.
Konohagakure has the ANBU Torture and Interrogation Force, who interrogate prisoners and work to gather intelligence. Though they were to officially disband, another ANBU group named the Foundation would carry out extremely secretive missions and were not under the direct authority of the previous Hokage.
The Medical Teams (Iryō-han) are the back-up of the shinobi forces. They consist of Medical Ninja, working behind the scenes to heal the sick and injured shinobi and to make sure the organisation is always in peak condition. Medical Ninja are also similar to a Hospital Corpsman or HM of the military in real life. They also do extensive research into new jutsu, medicine, and into diseases and the human body. Although not seen very often, they are highly respected. Even to a jonin, the advanced skills of these shinobi seem like magic.
Not all Medical Ninjas are members of the Medical Teams, though. There are also the Medical Ninjas within the regular forces, who go along on standard missions to increase the success-rate. However, back in the village, it is the Medical Teams who run the hospital and treat the wounded.