A wikia's founder is automatically given admin and bureaucrat rights during wikia creation. This allows them to edit the wikia's skin and format. As more contributors join, it's a good idea for bureaucrats to appoint trusted users as admins, rollbacks, and Chat Moderators.
The title of founder appears next to the founder's name even if they later abdicate their position as bureaucrat or administrator, and it overrides those titles.
Administrators (or "admins" or "sysop") are editors with extended rights that help them contribute to and modify the site. Voted into their position based on community consensus, Admins are granted their additional tools by a Bureaucrat. They are normally promoted for life, although they have the right to decline their tools or resign at any time. Administrators are expected to help other users when necessary and guide or correct them when necessary. Alongside their added tools and abilities, administrators are held to the same editing standards as other editors and are expected to follow the same policies as everyone else. Because of this, administrators are not beyond the rules of the wiki and can be demoted from their position if consensus deems it necessary.
Chat moderators are users who have chat moderator status in chat in order to moderate a wikia's chat room. They are able to block users from chat, which will kick a user out of the chat and ban them from returning until a chat moderator or an admin removes "Banned from chat" at Special:UserRights.
Active Chat Moderators
Inactive Chat Moderators
Past Chat Moderators
Moderators are users who have additional options available to manage thread conversations in the Forum and Message Wall features. They can remove and restore threads and replies from any user. They can also close and reopen threads. In the Forum feature specifically, moderators also have the ability to manage Forum boards, move threads from one board to another, and highlight and un-highlight threads.
Anyone can revert vandalism and bad-faith edits, but it takes a couple of clicks in the page history to get it done. Users with the "rollback" permission are able to undo bad edits with one click, by using the rollback link on diff pages, user contributions list, or the list of recent changes.
It is important to note that admins (including bureaucrats) already have rollback rights by default. The right can be optional for a user to have rollback and admin combined, but it will not add extra speed even with slower internet connections. Users with rollback rights are just users who are not necessarily an admin.
Rollbackers (users with Rollback rights) can be seen via Special:ListUsers, but they do not by default have any special title that appears on their userpage.
A "bot" is any automated process, program, or script that makes it easier for a user to make tedious or repetitive edits and actions on a wikia. When a bot is running in quick succession, the recent changes log can sometimes be overtaken, making it harder to spot more substantial edits by regular users. Giving an account a "bot flag" will hide these edits from the recent changes list (although any editor can still choose to see them by clicking "Show bots").
On Wikia, a user who wishes to use a bot should set up a separate account for it, then talk with other users on the wiki about whether the types of edits the bot makes should be hidden. After discussing it with the community, the bot owner or admin can request the bot be flagged.