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I've commonly seen references to a wheel user group online as well as when setting up my sudoers file. Does naming a group wheel imply something special about the group or is it just a name for a generic group used in the same manner that foo and bar are thrown about?
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Early on in the days of Unix one had to be a member of wheel in order to su to root. Used as an additional layer of protection for the system. I don't know of any special significance now, it is just a legacy like the uucp and dialout groups.
Rather than have to dole out individual permissions on a system, you can add users to the wheel group and they can gain access to administrator levels, simply by being in the wheel group. It's typically tied directly into sudo.
## Allows people in group wheel to run all commands
%wheel ALL=(ALL) ALL
Which means you can do anything on the system with sudo <cmd>.
Previously you needed to be in the wheel group if you wanted to have access to use certain commands, such as su.
excerpt - Wheel on Wikipedia
Modern Unix systems use user groups to control access privileges. The wheel group is a special user group used on some Unix systems to control access to the su command, which allows a user to masquerade as another user (usually the super user).
