Administrators are users who have been entrusted with additional sysop (system operator) privileges to better aid them in maintaining the site, including:
- Deleting and undeleting pages, page histories, files, etc.;
- Renaming files;
- Locking (protecting) pages;
- Blocking IP addresses or user names from editing;
- Reverting bad edits more easily using a "rollback" link;
- Editing the MediaWiki namespace to make changes to the interface.
Bureaucrats are administrators with the additional ability to manage users' rights when necessary.
For a complete list of users who have sysop rights, see Special:ListUsers/sysop.