NET COMPUTER adds or deletes computers from a domain database. This command is available only on Windows NT Servers. \computername ...

NET COMPUTER adds or deletes computers from a domain database. This
 command is available only on Windows NT Servers.

\\computername    Specifies the computer to add or delete from
                  the domain.
/ADD              Adds the specified computer to the domain.
/DEL              Removes the specified computer from the domain.