Groups are, of course, the answer to administering various users and their access to system and enterprise resources. If you are familiar with Windows NT 4.0 groups, the changes won't be too bad, but they are significant. If you're learning Windows administration for the first time, don't bother reading Windows NT 4.0 administration books because it's changed. When I refer to a user , I mean the user account that the user logs onto. A group is a collection of users that permissions are assigned to.
Groups provide an easier mechanism for administering the rights of users.
Instead of assigning the rights to each user, they are assigned to the group. All users in that group inherit those permissions. The administrator need only place a user in a group to grant him access to the resources that the group already has. Windows NT 4.0 has its own concept of a domain, different from DNS domains. The NT domain is the security accounts database the primary or backup domain controllers maintain.