What features are missing in Windows Server 2003 Web Server?

Windows Server 2003 Web Server is for web serving and hosting

The follow features are not included in this edition: Enterprise UDDI Services, Cluster Service, Session Initiation Protocol Service (SIP), Internet Authentication Service (IAS), Network Bridge, Internet Connection Sharing (ICS), Metadirectory Services (MMS) Support, SharePoint™ Team Services, Removable and Remote Storage, Fax Service, Services for Macintosh, Remote Installation Services (RIS), Windows Media™ Services, Internet Connection Firewall, Terminal Server, and Terminal Server Session Directory