CommunityData:Wiki
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Making someone an admin
In general, anybody who is not a spambot should be made an administrator or a sysop (it's the same). Admins don't have to solve CAPTCHAs (hooray!) and can delete pages and such.
Anybody who is part of the group should be made a bureaucrat as well. Bureaucrats can make other people into admins.
To make someone an admin you navigate to the Special:Userrights page, type in the username (like Special:Userrights/Benjamin Mako Hill) and then add the appropriate bits by checking the boxes.