Desired State Configuration is a new management platform added in PowerShell 4.0 that lets you manage your servers’ configurations more easily. Instead of writing a “setup” script that goes and checks for perquisites and installs them if they’re missing, you create a script that expresses how the server should be configured. When you run the script, the DSC framework is responsible for enforcing that the server’s configuration matches up with what you defined, only taking the minimum set of actions necessary to enforce that state.
DSC is built off of the Managed Object Format (MOF), which is the language used to model Windows Management Instrumentation (WMI) interactions. Don’t worry about MOF too much for today, though!