In Microsoft Windows NT and Windows 2000, a type of group created during installation to simplify the delegation and assignment of common administrative tasks. Built-in groups have preassigned sets of user rights, and some also have preassigned members.
Windows NT contains three kinds of built-in groups:
Built-in local groups: These are used to assign predefined sets of rights and permissions to users and groups of users, and they exist on all computers running Windows NT.
Built-in global groups: These groups are used to automatically organize users into common groups for administrative purposes, and they exist only on Windows NT domain controllers.
System groups: These are used by the operating system to automatically group users for system purposes, and they exist on all computers running Windows NT.
In Windows 2000, the built-in groups are similar in function, except that a fourth type, called a domain local group, is also available. Built-in groups in Windows 2000 are also administered differently using different tools. Also, system groups in Windows 2000 are referred to as built-in identities.
You cannot rename or delete a built-in group, and you cannot change the membership of a system group.