In Windows Server 2012, Microsoft made it easy to add and remove the graphical user interface (GUI) using simple powershell commands. Running a server without the overhead of the GUI (called Server Core) helps keeps the server more secure since less programs are running that could be exploited. Running without a GUI should also help limit the number of reboots required every Patch Tuesday, but in truth I haven’t yet seen that many reductions in reboots on my Server Core systems.
To install the user interface, open powershell and type the following cmdlet:
Install-WindowsFeature Server-Gui-Shell, Server-Gui-Mgmt-Infra
Similarly, you can uninstall the user interface with the following cmdlet:
Uninstall-WindowsFeature Server-Gui-Shell, Server-Gui-Mgmt-Infra
Of course, running these cmdlets will require a reboot to finish the configuration.