Windows Server 2012, is the next installment of the server system, based on the kernel and appearance of Windows 8. This system, after too many interface novelties, has more than 2300 commands in this version of Windows PowerShell compared to about 200 in Windows Server 2008 R2. The emphasis is on making sure that PowerShell can perform any action from the administrator GUI (such as can be "clicked"). The system contains features and improvements known from Windows 8.
New features of Windows Server 2012:
New Metro user interface known from Windows 8
Possibility to switch between Server GUI and Server Core interface options without reinstallation
Redesigned Task Manager
Improvements of Active Directory, Hyper-V and new IIS 8
New licensing model
Windows Server 2012 is only available in 4 versions:
Foundation - license limited to 1 processor, available only through OEM
Essentials - Limited to 2 processors, higher limits than Foundation. Available in retail, VL and OEM. System offers basic server functions.
Standard - adds Hyper-V, Server Core, ADFS and uses CAL license. Available in retail, VL and OEM. Normal version of server system.
Datacenter - unlimited virtualization rights, system designed for data servers. Available only through VL or OEM