Windows Server “Longhorn” Core is a much smaller, command line based operating system which has no user interface except for a command line and the wallpaper. It’s about 500MB in size because it doesn’t have any of the eye candy that Windows Vista has. The server core can still handle many of the server roles that Windows Server “Longhorn” has, such as DHCP server, DNS server, Active Directory and File servers. It also can handle subsystems for UNIX based applications, network load balancing, BitLocker volume encryption, backup and removable storage.

The good thing about Windows Server “Longhorn” Core is that it can be run on a very basic computer. Pentium 3 800Mhz, 256MB RAM, 5GB hard drive, onboard sound and graphics - it can run because it’s such a simple operating system, yet still powerful enough to maintain an entire network.

As described on the “Longhorn” Server Core TechNet blog, “Server Core is all about letting an administrator run the above roles with less installed, running, and needing to be managed on a server. For example, there is no GUI shell on Server Core, the local interface for managing the server is the command prompt. You can use MMC snap-ins to remotely manage a Server Core installation. All of this provides the following benefits including reduced maintenance, reduced attack surface area, reduced management and less disk space required to install”.