A Core install of Windows Server 2008 has no Explorer or MMC, but it's not character mode either

posted by  hjwin (10)  11 months ago (blogs.technet.com)

Everyone that is experimenting with Windows Server 2008 is excited about the Server Core installation, which is a minimal install of the Server that can run specific roles (like DNS, Active Directory or File Server) with a much smaller footprint and attack surface. A Core install is indeed much smaller than a Full install both in memory and on disk. In fact, if you install both versions using Virtual PC, the difference in size between the two resulting VHD files is quite dramatic. Using the Windows Server 2008 Enterprise Beta 3 my VHD size was about 5.9 GB for a Full and only 1.6 GB for the