Here is a better way to explain the ranks. I found them at a cool Mob website.

Capo Crimini (Super Boss):
The most powerfull boss in the world. I doubt this is used at all, except for maybe the media.

Capo Di Tutti Capi (Boss of Bosses) :
The Capo Di Tutti Capi is the most influencial Don of all the Dons. This position is no longer used really, except for who the public thinks is the most powerfull figure in organized crime. The Capo Di Tutti Capi normally heads the Cupola (Commission) meetings where all the Dons meet to discuss inter family disputes, war/peace, rackets, and territories.

Capo / Don / "Godfather"(Boss):
The Don is the head of the family, no one can call the shots over his decisions. He is also only 1 of 2 people who can initiate someone into the family. Since his rank gives him the authority to give the oath to new members and make them sgarrista.. He also has the authority to give people their positions and ranks.

Sotto Capo / Capo Bastone (Underboss):
The Underboss is appointed by the Don. He is the second in command of the entire operation. He is usually the leader of "day-to-day" functions..Hes the muscle on the street. His word should go unchallenged by everyone except the don. He is basicly the top dog when it comes to the work on the street. The Don goes to him for "orders" and "jobs". He is also to see to it that the Caporegimes stay in check. Underboss is the only other person who has the authority to swear in new members, but he must report them to the don.

Consigliere(Counselor / Advisor):
The Consigliere is voted by the whole family(made members). In theory, the consigliere is the same rank as the underboss. Yet the consigliere has no power in the "day-to-day" operations. He is only there to advise and sometimes question. He is the equal rank of underboss but does not have the authority to give any orders. His job is to advise on all of the don's decisions and some of the underboss's. He is the only one in the family who is allowed to speak his mind on all important matters and even question the don, yet can not override him.

Caporegime(s) (Crew boss / Captain / Capo / Lieutenant):
A Caporegime is appointed by the Don, and is in charge of his own borgata(regime, or crew). Which is made up of a Capodecine and soldiers. Each Capo reports directly to the Underboss or Advisor for permission to do different things. When someone is needed to be "taken care of" the capo's are usually asked to carry out the order. They are the head of "day-to-day" operations of their own crews. The capo heads a crew of any given number of soldiers. These soldiers give the Capo part of their earnings, and the Capo gives part up to the Underboss or Advisor. Caporegimes are also the ones who may ask and recomend certain men to be sworn into their crews. When this happens they must ask the underboss or the don himself. In a sense, crew boss's are head of the "Street Side Gangs".

Sgarrista / Soldato (High Soldier / Soldier / Wiseguy / Button / Buttonman / Goodfella):
The Sgarrista is "made" into the family by the Don or Underboss after being voted for by the captains and up. One of the biggest honors in La Cosa Nostra(This Thing Of Ours) is to be initiated into a family. When you take the oath and our sworn in under the blessing of either the underboss or the don himself, you become a "Sgarrista"(Soldier) and you are a "Made Man". When you are "made" which is taking the oath, you become a part of the family, you become one of us. Even though you are one of the lowest rank in the "real" family, you still have alot of power over associates and friends. You are assigned into a crew and given a capodecine. From then on, your captain and\or caporegime will give you orders and jobs. When your a soldier..You are commonly mentioned as "a friend of ours".

Picciotto(Low Soldier):
The Picciotto is "made" into the family by the Don or Underboss after voted by the captains and up. Sometimes this position is not used. When you are "made" you attain the rank of picciotto, which is the rank of soldier(read the definition of sgarrista)..but lower class soldier. When you show that you are a good earner, and buisinessman you will attain the rank of sgarrista ). I don't think this is used at all, except maybe in the sicilian mafia, i am not totaly sure.

Giovane D'Honore Associates(Non-Made Members / "A friend of mine" / Associate):
When your a "made man", or any other rank for that matter, you may have buisiness dealings or partnerships with non-made people. These are "associates" commonly refered to as "friends of mine" when mentioned in buisiness meetings. So the bottom line is all non-made people who have dealings with the family, are associates\friends. They have no power in the family.
There can be "members" who are not "made" into the family.. They can not attain any other rank until they are "made". They are just guys who run with the crews in day-to-day operations, normally working for a soldier.