Nano Server is even more stripped-down than Windows Server Core with the GUI stack, 32 bit support (WOW64), MSI and a number of default Server Core components all being put in the dustbin.

You can't do local logons, Remote Desktop and WMI and PowerShell are the only tools available to manage the creature.
Microsoft is also working on better remote tooling and is coming up with a set of management tools for the nano. It is planning work on PowerShell's Desired State Configuration, file transfers and script authoring and debugging.

Cutting all this stuff out has made it more efficient, secure and availability. Redmond said that the Nano Server has 93 percent lower VHD (Virtual Hard Disk) size.

It also gets 92 percent fewer critical bulletins and requires 80 percent fewer reboots than a typical Windows Server. It is also a bit quicker to setup: from bare metal to running Nano Server takes 3 minutes.

Hyper-V containers also will offer the system a fair bit of isolation that was only available to "dedicated physical or virtual machines".