Ranks are people who have rped well enough to have an actual rank in the game. ranks vary on each planet and for each race. Rankers are the only ones who can rank you besides earth guardian who grants korin. Also each rank comes with several skills and upgrades
Turtle hermit- Gains the move of master roshi and is 20 years older
Crane Hermit- Gains the moves of the crane hermit (kihoko and dodompa) and is twent years older.
Earth Guardian-Basically has to defend the earth at all times. If namek it can create dragon balls.
Korin- Plants senzu beans and guards holy water.
King of vegeta- Rules vegeta (can be male or female).
Tuffle Scientist- Gets intel boost and has no real purpose.
Namekian elder- Rules over the namekians
Lord of icer- Becomes a lord of icer
If you ask and rankers agree you can be given a custom rank of your choice with a modest upgrade of skills intell or whatever your rank requires
Teacher and skill master
Both ranks are given a variety of skills depending on the planet your on. Unlike skill masters teacher need students at all times.