A DSC resource is a specially created PowerShell module that enables DSC to configure various aspects of a node. The WindowsFeature DSC resource, for example, enables you to ensure that a particular node of a particular Windows feature installed. You could also specify that a particular Windows feature should not be present.
As you have seen in this chapter so far, Windows comes with a few DSC resources built in. But these do not provide broad coverage. For example, you can use the built-in File resource to copy the source files for a small web application onto a new server. But the built-in resources do not allow you to specify the application's settings (what the application name is, which application pool it runs in, and so on) which is where add-on DSC resources come in.
The community, which includes various Microsoft teams, has been...