Installation option for Windows Server starting with Server 2016. This mode lacks a local console and can only be managed remotely.
Nano Server is a new installation option for Windows Server 2016 and later. There is no GUI whatsoever, therefor there is no console and a local logon to the server is not possible. With no GUI, remote desktop is also not supported. All administration has to be performed from remote machine using Server Manager or other tools. A special version of PowerShell, PowerShell core is available but doesn't support all features of the full version. Remote PowerShell sessions into the server are supported.
A new web based administration system will be included.
The 32Bit subsystem (WoW64) has been removed, so 32bit programs will not run.
The disk and memory footprint is much smaller than for traditional installations of Windows Server.
Only certain server roles are supported.