Welcome to Gaia! ::

In the series of Naruto a jutsu ("Technique" or "Skill" in Japanese) is a general term referring to any technique a ninja might use that not any ordinary human could naturally imitate.

Jutsu are usually the product of channeling chakra to a certain part or parts of the body (through the inner coil system, which is to chakra as blood vessels are to blood) and then manipulating it to create an effect which wouldn't be possible otherwise. If the inner coil system malfunctions or is blocked in any way, it is impossible to perform any jutsu at all.

Basic information
Generally speaking, jutsu are divided into three categories: Taijutsu (Body techniques), Genjutsu (Mind techniques) and Ninjutsu (Techniques that rely on sources beyond those). Besides these main categories there is another, more specific category: Fūin jutsu (Sealing techniques).
Besides being either Ninjutsu, Taijutsu or Genjutsu a jutsu can also be "Hiden" ( Secret). Hiden jutsu are jutsu passed down from generation to generation within some clans.

There is technically another category called Kinjutsu (Forbidden Techniques), but it refers not to the type of the jutsu but to the fact that it is forbidden to learn or perform it. A technique can be categorized as kinjutsu if it either causes great harm to the user if overused, such as Rock Lee's Lotus techniques, or if the techniques are dark or sinister in nature, such as many of Orochimaru's skills.

There are also Kekkei genkai. These are not really jutsu, but special, genetically inherited abilities like the ability to copy other jutsu or to merge your body with other bodies. Kekkei genkai abilities that work via the user's eye are called Dojutsu (Pupil Techniques). Some jutsu are based on Kekkei Genkai, like Tsukuyomi.

The known ninja ranks that can be obtained by a ninja.
Academy Student
Genin
Chuunin
Jounin
Special Jounin
Kage
ANBU
S-Class
Medical-nin
Hunter-nin
Missing-nin
Courier-nin
Cooking-nin

Ranking
There are seven different ranks in jutsu:
S-rank: Secret: extreme level jutsu
A-rank: Kinjutsu: ultra high level jutsu
B-rank: Jounin level jutsu
C-rank: Chuunin level jutsu
D-rank: Genin level jutsu
E-rank: Academy student level jutsu
No rank: Jutsu relying on the unique abilities of the users (Kekkei genkai, Hiden jutsu)

Mission Ranks
A-Rank
These missions are done by Jounin rank ninjas and usually include important tasks including assassinations, escorting important people..etc.

B-Rank
These are completed by Chuunin rank ninjas.

C-Rank
These are completed mostly by Chuunins but are sometimes done by Genins.

D-Rank
This is the lowest class mission that can be completed and are usually done by Genins. These missions are usually small priority.

Bloodlines
Kekkei Genkai
Byakugan
Sharingan

Weapons Guide
(Some wepons at the links above)