Server Core

The big change occurred in Windows Server 2008 and Microsoft introduced Windows Server Core as an installation option. This was really the first step toward having to deploy less on your servers, have less that you have to patch and reboot, and have fewer components that you don't necessary need on your servers. What I mean by the installation option is, when you first start installing the operating system, you have the option to choose between Server Core or Server with Desktop Experience installation.

Once you deploy Server Core or Server with Desktop Experience, then you can start adding roles and features that you want to run on top as shown in Figure 1, small boxes on top.

For Windows Server 2008 and Windows Server 2008 R2, the choice between Server Core and a full installation had to be made at installation time and couldn't be changed without reinstalling the OS:

However, with Windows Server 2012 and 2012 R2, Microsoft has offered the installation options in a way that you can start by deploying Server Core. Then there is a package that you can add to move up to Full Server or you can install a Full Server and then remove the server graphic shell and Graphical Management Tools and Infrastructure and convert back down to Server Core is as showing in Figure 2. In other words, the graphical shell and the management infrastructure are features that can be added and removed at any time, requiring only a reboot, making it easy to switch between the Server Core and Full Server with GUI. Microsoft also introduced the minimal Server interface so you can actually uninstall Internet Explorer and Explore.exe and have just Microsoft Management Console ( MMC) and Server Manager, which results in less patching. The Minimal Server Interface has fewer benefits than Server Core but it does provide a nice middle-ground versus Server with Desktop Experience: