Shinobi

otherwise referred to as in the English translations of Naruto, are the primary focus and the main military power in the series. A female ninja is a kunoichi. Most come from a hidden village and will perform missions for a fee. These missions can include: doing manual labor, acting as escorts, gathering secret information, retrieving stolen items, carrying out assassinations, etc. In times of war, ninja will come together to defend their villages and land. The clearest characteristic of a shinobi is their ability generate and control chakra to create a jutsu.

Jutsu
Shinobi can use a variety of jutsu, techniques often based on the utilization of chakra. This allows shinobi to perform extraordinary things. Jutsu are separated into three groups, Ninjutsu, Genjutsu, and Taijutsu. Ninjutsu implies perform a supernatural or beyond normal ability, the most common of which is the elemental jutsu. These are created by the user transforming their chakra into a specific nature or 'release'. The chakra types are Lightning, Earth, Fire,Wind, and Water. Other sub-types of chakra natures such as Wood Release and Ice Release also exist, created by combining two of the basic five releases. Taijutsu implies physical techniques, which may or may not require chakra. Certain shinobi such as Rock Lee lack the ability to mold chakra, leading them to become masters of Taijutsu. Genjutsu creates illusions, things that the foe believes to be real that are in fact fake. Genjutsu is the least-used of the three groups, possibly due to the difficulty required in performing the techniques.

Tools
Ninja tools are used as alternatives to jutsu. They can include weapons, accessories, and even clothing. Ninja such as Tenten have mastered the use of such tools. A standard shinobi will have a pouch equipped with many such tools, and nearly every ninja is equipped with at least a shuriken holster.