Server Admins
Admins are responsible for running and maintaining the server. They have full server access. Admins never use their commands to gain an unfair advantage, they plan the game just like everyone else.
Game Moderators
Game Moderators are "champions of the community". They enforce the rules, help players, and assist the admins with creating rules, running events and more. They can check block data, perform rollbacks, teleport, ban players and more. Moderators never use their commands to gain an unfair advantage, they plan the game just like everyone else.
Chat Moderators
Chat Moderators enforce the chat rules and help new players. They have access to /kick and /mute.