Genin

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. Due to the fact that genin are the lowest level ninja, they are normally assigned D-rank or C-rank missions so as to gain experience before taking on harder missions or being promoted to the rank of 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 are fit to become chūnin.

Trivia

 * The anime shows Might Duy and Might Guy living poverty due to Duy getting paid for mostly for D rank missions; this implies a Genin's salary is only enough to provide for themselves.
 * A shinobi's rank doesn't necessarily reflect their abilities, as such, Naruto despite being a genin, was selected to become a kage. He admitted to Team 5 that he was still a genin at the time of his selection to become Hokage (having failed in his studies to get promoted to Jonin) due to circumstances prevented him from taking the Chūnin Exams beyond the first and only one he ever took.
 * Similarly, Kosuke Maruboshi, who is called the has the skills of a jōnin-level shinobi, but is officially a genin — a rank he had consciously decided to remain at, due to personal reasons. He shares the epithet with Might Duy, who in his twenty years as a genin mastered the Eight Gates.
 * In addition, should a Genin like Naruto have exceptional abilities, he can be sent on any ranked mission and not just D and C rank; therefore earning an average ninja's salary. (This would explain why his family lived in better conditions that Guy's; unless they had support from the Hyuga Clan.)