How are passwords, users, and groups managed on Mac OS X?
One way Mac OS X differs from other UNIX implementations is that passwords, users, and groups aren’t managed by the normal files in /etc you may be familiar with. All these tasks are managed by NetInfo, a sophisticated network, directory, and user management system. NetInfo Manager is very powerful, and beyond the scope of this document. It can be found in /Applications/Utilities/NetInfo Manager. For a basic introduction to NetInfo, see What is NetInfo? and Understanding and Using NetInfo. Mac OS X is slowly moving toward the new Open Directory and LDAP for directory services.
