[His smile grows a little more subdued; that's pretty much exactly why he's here now. Being lost in the mist..... He just can't stand it. He needs to have something to guide him.]
Oh, ah--Genin is the lowest rank a ninja can have, aside from being an Academy student. Once you graduate, you're placed on a team with two other Genin and a Jounin teacher, who continues to give you more specialized training as you work in the field with less dangerous missions and improve your skills. You stay with your team until you're promoted. Jounin is the highest rank you can formally have, aside from being a Kage--those are the leaders of their respective villages.