By removing the graphical user interface (GUI) of the operating system and features like 32-bit support, MSI and various default Server Core components, Windows Nano Server can deliver greater speed, stability and security, as well as dramatically reduce resource consumption.
This leads to real-world benefits such as 93 percent lower VHD size, 92 percent fewer critical bulletins, and 80 percent fewer reboots in testing compared to the full Windows Server operating system.
Nano Server versus Server Core
While Nano Server shares similarities with the Server Core option introduced in Windows Server 2012, Nano Server is even leaner than Server Core (twenty times smaller than Server Core) and is optimized for use with the modern cloud. Microsoft sees two distinct scenarios where Nano Server would be an ideal fit:
Nano Server was first made available in preview as part of the Windows Server 2016 Technical Preview 2 release following initial development under the codename Tuva. Nano Server will officially debut in conjunction with Windows Server 2016 in the second half of 2016.