From Microsoft Windows NT Server Basics and Installation (Start Here) Guide:

"Windows NT Server is also the easiest network operating system to set up,
manage and use."  (page 3)

"Windows NT Server is the only network operating system that includes
Internet and intranet capabilities."  (page 3)

"Windows NT Server is the only network operating system that has been
certified by the U.S. Government.  All information, whether accessed
via NetWare, Windows NT Server, Macintosh or Web-based protocols, is
subject to this security.  Because of its integration with Windows NT
Server, the Internet Information Server provides the same level of
security.  (page 4)