Bureaucrats are administrators with the extra power of upgrading or downgrading other people's powers. In this way they lead the wiki, encouraging the people around them, keeping order up to the highest extent.
Administrators are normal editors who have been entrusted with rollback rights. They can protect and delete pages, and block other editors. Please note that they do not own the wiki in any way and are equal to other editors in terms of responsibility for wiki articles.
Helpers are trusted editors who are granted rollback rights, they can't yet delete or protect pages. They are picked by the higher staff members based on their hard work and their overall trustworthiness.