Datacenter and Standard editions provide: The packaging and licensing structure for Windows Server 2012 R2 editions remain unchanged.  Foundation edition for small businesses with up to 15 users running on single processor servers.

 Essentials edition for small businesses with up to 25 users running on servers with up to two processors.  Standard edition for non-virtualized or lightly virtualized environments.  Datacenter edition for highly virtualized private cloud environments. The Windows Server 2012 R2 product is streamlined and simple, making it easy for customers to choose the edition that is right for their needs.

It lets you build, run, and scale applications that can move between your datacenter and the cloud, and it allows you to provide your users with flexible remote access from virtually anywhere and any device while helping protect corporate information. It reduces complexity and cost with comprehensive automation plus storage and networking virtualization solutions based on industry-standard hardware. It lets you optimize performance for your most important workloads and helps protect against service outages with robust recovery options. Windows Server 2012 R2 captures Microsoft’s experience of delivering global-scale cloud services to provide an enterprise class server and cloud platform.

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