Intro
Techniques (also known as Jutsu) are the arts that ninja use in battle. In order to perform a jutsu, the ninja will need to apply his chakra.

The chakra can come from two places: your cells and mental & spiritual energy gained from experience. The ninja will release these two energies before performing a jutsu. Soon after that, the hand seals are formed and the creation of the desired jutsu is started.

Jutsu are ranked depending on the difficulty or skill needed to perform them. In total, there are 6 ranks plus two additional informal ranks for special situations. The rank of a jutsu doesnt necessarily mean that it will be more effectice than a lower-ranked jutsu, but just more difficult to perform properly. The informal ranks are Hiden jutsu and Kinjutsu.

Hiden jutsu are jutsu that has been passed down from generation to generation within a clan. These jutus are not ranked since no one outside the clan knows how to perform them. Kinjutsu sometimes fall into one of the six main ranks, but there are some exceptions because they are forbidden (or looked down upon) to learn and perform.

Some things that usually indicate if a technique is categorized as forbidden is if it causes great harm to the user (such as opening the eight gates), or if they are sinister in nater (such as the revival jutsu performed by Orochimaru).

The Six main Jutsu ranks are:

E-ranks - Academy Student
This is where would-be ninja would start. They are not considered ninja, however, until they graduate. The academy students take tests both formal and practical in addition to being taught martial arts, techniques, and basic ninja skills. Basic weapon usage is commonly taught, and the elementary ninja techniques are taught also.

D-Rank - Genin
This is the lowest level of the ninja and also the ones that display the most difference in power. When the ninja become Genin, they do missions that benefit the villages economy. They are typically sent on D-rank missions (the lowest mission rank). These missions are usually risk-free and potentially offer little to no harm.

C-Rank - Chuunin
Chuunin are the ninja who qualify to watch over and guide the other ninja. They have reached a level of maturity that mostly consists of leadership skills and tactical prowess. In order to become a Chuunin, a Genin participates in a large exam with his or her teacher.

B-Rank - Jounin
Jounin are highly-experienced ninja with great skill who serve as military captains. They are usually sent on A-rank missions, and experienced Jounin can even be sent on S-rank missions. They are sometimes assigned as sensei for three-person teams of Genin.

A-Rank - Kage/Jounin
Those who have achieved the title of Kage are the leaders of the five most powerful hidden villages and also the most powerful ninja in their respective villages. Most Kage have family members who were previous Kage, or personally taught by a former Kage.

S-Ranks - Serious/Extreme
S-Class ninja have gained far more power than the average Jounin. The title is more of a class rather than an actual rank though. The relationship among these ninja vary from being part of the village to a ninja who wonders, but still maintains loyalty to their village such as Jiraiya.

Elements & Jutsu
The jutsu a ninja uses are base of various elements. The five main elemental styles are also the five names for the five great shinobi countries (fire, wind, lightning, earth, and water). Each ninja has the potential to use a style better than the other or more. A special elemental detecting paper is used in order to determine ones type. The paper comes from trees which are specifically grown with chakra. When a user channels a portion of their chakra to the paper, the paper will react and reveal the users type. If the users type is Fire, the paper will burn. If the users type is wind, the paper will split in two. If the users type is Water, the paper will become wet. If the users type is Lightning, the paper will crumple. And if the users type is earth, then it will fall apart.

Each of the five elements contain a strength and a weakness. The fire element is stronger than the wind element. The wind element has an advantage over lightning. Lightning has an advantage over earth. Earth has an advantage over water, and water finishes the cycle off by finishing out fire.

Types of Jutsu

Cursed Seal Jutsu
Cursed seal jutsu are jutsu that use a special "cursed seal" to put the opponent under control. A prime example of this would be when Orochimaru initially planted his curse seal on Sauske during the Chuunin exams.

Fuuinjutsu (Sealing Techniques )
Fuuinjutsu are sealing techniques the ninja uses. They enable the ninja to contain the element and demons. Examples of this type of jutsu would be when Shukaku was 'placed' inside Gaaras body via Fuuinjutsu technique.

Ninjutsu (Ninja Techniques)
Ninjutsu is usually almost any technique that requires chakra, and allows the user to do something that they otherwise would not be able to do. While Genjutsu makes the opponent see illusions, the effects of ninjutsu are very real. Ninjutsu relies strongly on chakra and most of the time, hand seals. The hands are formed in different positions that shape the chakra into the needed manner to perform the jutsu.

Taijutsu (Body Techniques/Hand-to-hand combat)
Taijutsu is associated with any techniques that involve martial arts or the use of human abilities in general. Taijutsu is much more easier to execute than Ninjutsu or Genjutsu because it is executed by taping directly into the users stamina, rather than converting the users stamina to chakra. Although chakra is never used in taijutsu, there are some exceptions. The Hyuuga clan uses chakra in their Gentle Fist style of attacking, and Tsunade and Sakura combine chakra into their attacks in order to deal more damage.

Genjutsu (Illusion Techniques)
Genjutsu techniques are the illusion techniques of a ninja that normally require hand seals. Genjutsu will use hypnosis to cause hallucinations in the opponent. By using such realistic illusions, they can cause their target mental pain that is just as real as taking physical damage. Genjutsu is created when a ninja releases their chakra flow from the cerebral nervous system of their opponent, controlling their minds chakra; thus, affecting all five senses.

Depending on the user, countering Genjutsu could be difficult. But there are two options to counter Genjutsu. The first option is to stop the flow of chakra in there body, applying an even stronger force to 'override' the casters flow of chakra. The second way is to have an outside user who is unaffected by the Genjutsu use their chakra to disrupt the casters chakra flow.