These are the Groups & Ranks of the forum.
Groups
▪ Administrators
▪ Super Moderator
▪ Yoshi Forum Moderators
▪ Off-Topic Moderators
Ranks
▪ Admin/Post: Special
▪ Moderator/Post: Special
▪ Super Moderator/Post: Special
▪ Site Designer/ Post: Special
▪ Official Yoshi Fan/ Post: 50
▪ Junior Member/ Post: 0
Special means that the Admin has to assign you that rank.
So if you wanted to become and Mod then you will have to ask an Admin to be one.