There is a new keyword called partial. It tells you a class definition is in multiple files. Next there is XAML for the UI. It stands for eXtensible Applicaiton Programming Language. It is based on XML. While we are talking about buzzwords, let's defined WPF. Previously this was called WinFX. It is part of the .NET framwork 3.0. It stands for the Windows Presentation Foundation. Whew.
Now let's talk about a Grid. This is a panel. In fact it is derrived from the Panel class. The thing acts as a container. You can like this to an HTML table. You build your apps with Visual Studio. That deploys them to Windows 8. Then you can launch them from the Start Screen.
You place elements on your UI. These are things like text blocks or images. They are not controls per se. You use the elements to build controls. XAML creates the controls for you. Or you could opt to do it just with code. Function MainPage() creates the controls. The XML gets parsed during compile time. That generates a source file.
Charles Petzold, in his book, recommends you use XAML. But you don't have to. You can create a new app. You must handle the OnLaunched event. You can just use the context yourself to handle everything. I never did though.
