Windows 2000 Server: How to join a domain

Domains are part of larger, centrally administrated networks. Install your computer as part of a domain if any Windows 2000 Server on your network are configured as domain controller with the Active Directory installed. To join a domain, you must specify the name of a valid domain and provide the username and password of a user who has rights to add a computer to the domain. Both a DC for domain and a DNS server must be available to authenticate the request to join the domain.