Resident/CannonFodder/Survivor/Freebuilder depending on the server you are on. All new members of Muttsworld are automatically Residents.
Diplomat/Infected - Comes with extra perks such as diplomat chat, private warps, and extra plots. Perks are different for each server but
purchasing diplomat will allow you the rank on all servers.
Available for purchase on the store http://muttsworldmine.com/forums/store
Ambassador - Chat moderator and newbie integration. They hold the power to mute and enforce server rules when a mod is not available.
Moderator/Mod - Rule enforcer and event organizer. The server police. They answer your modreqs and resolve conflicts between players.
Admin - The bosses. They run the server.