In Windows 2000 Professional, users and groups are created using the Computer Management tool’s Users and Groups extension. By default, W2K Pro still only includes two user accounts by default, Administrator and Guest. Similar to NT 4, the Guest account is disabled by default. Both accounts can be renamed, though neither can be deleted. A number of built-in groups also exist by default, some of which allow you to control membership (local groups), and some of which control membership automatically (system groups). The table below outlines the built-in groups you will find, but of course you can still create your own local groups.
Built-in Local Groups:
Administrators
Backup Operators
Guests
Power Users
Replicator
Users
Built-in System Groups:
Anonymous Logon
Authenticated Users
Creator Owner
Dialup
Everyone
Interactive
Network