During installation, you must choose the type of network security group that you want the computer to join: a domain or a workgroup.

Joining a Domain

During installation, you can join an existing domain as a member server. Joining a domain during installation requires the following:

Joining a Workgroup

As with Windows NT 4.0, you will only join a workgroup if you are in a small network without a domain, or if you are preparing to join a domain later on. The workgroup name that you assign can be the name of an existing workgroup or the name of a new workgroup that you create during installation.