Genin (下忍, 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.
Genin are put in four-man cells or squad, consisting of three genin and a jōnin-sensei, in order to learn teamwork and experience true ninja life under the supervision and protection of an elite shinobi. The make-up of these teams is based on the individual skills of the genin, so that there will be a balance between the teams. For instance, Naruto Uzumaki, who passed with the lowest grades, was put in a team with Sasuke Uchiha and Sakura Haruno, who passed with the highest grades and highest written exam scores, respectively. The teams are usually made up of two boys and one girl.
Due to the fact that genin are the lowest level ninja, they normally provide limited use during dangerous missions (B-rank or higher), and are usually only capable of successfully completing E-rank or D-rank techniques. However, it should be noted that genin is simply a rank, and is not always an accurate representation of a ninja's skill level. Naruto Uzumaki is still a genin, but regularly goes up against the S-rank criminals of Akatsuki. Naruto was also able to defeat the extremely powerful Pain(throught the use of the nine tailed fox) whereas the highly ranked ninja such as jōnin Kakashi Hatake and Sannin Jiraiya were not and were consequently defeated and killed. Another example is Kosuke Maruboshi, who is called the Ten-Thousand-Year Genin (万年下忍, Mannen Genin) has the skills of a jōnin-level shinobi, but is officially a genin.
Though genin are relatively low-levelled ninja, they can progress to become a chūnin, by successfully completing the chūnin exams, a set of difficult tasks made to test the skills of genin to see whether or not they should be chūnin.