Could someone explain to me the following?

Question

In addition the Mobile PC User Experience Guidelines for Developers describe how you can optimize the computing experience for your mobile PC users by following established user interface design principles in your application, whether or not the application is designed specifically for mobile computing scenarios.

Answer 1

They're saying that they have some generic guidelines for UI construction that will allow applications to be easier to use on Mobile PCs -- and that those guidelines can be used even for applications that are not designed (solely) for Mobile PCs.