Microsoft released Windows Server 2016 on January 12, 2017, you can download the evaluation version

https://www.microsoft.com/en-us/evalcenter/evaluate-windows-server-2016

or download from your MSDN Library

some new feature from this version:

Strengthen your security—starting at the operating system

Help prevent malicious attacks and detect suspicious activity where it matters: your operating system and workloads. Rely on security features built into Windows Server 2016 to control privileged access, protect virtual machines, and harden the platform against emerging threats.

Be more efficient with a software-defined datacenter

Bring flexibility and control to your datacenter while lowering costs with software-defined compute, storage, and networking. Run your datacenter with an automated and resilient operating system, and access many of the same cloud-efficient features found in Microsoft Azure datacenters.

Innovate faster with cloud-ready application workloads

Securely deploy and run your existing applications on Windows Server 2016 to transform them into new cloud-native models. Help developers to innovate and create on-premises and cloud applications using the latest technology—containers, microservices, and Nano Server.

and to learn about new version, you can get from MVA Training