The Model-View-View-Model (MVVM) pattern is held in high regard by many developers as an excellent way of creating sophisticated modern applications. It's clear seperation of presentation and business logic produces a clean implementation that promotes speed, scalability and code reuse in applications with a complex UI. These strengths have found it favor with WPF and Silverlight developers. It is now increasingly being employed for Windows 8 apps, a purpose to which it is ideally suited as this book will show. In this brief, information-rich, guide we will show you how MVVM works with both XAML (C#) and HTML5 (JavaScript) flavors of Windows 8. Beginning with a brief recap of MVVM concepts under .NET - to provide a common frame of reference - we will then delve into the details of how MVVM can best be implemented in Metro-style apps for Windows 8 and show a working application framework in each case. What youll learn How the MVVM pattern can bring elegance, power, speed and reusability to your Windows 8 apps. That MVVM implementations under Windows 8 differ from MVVM implementations under .NET. Produce fully working Metro-style applications using XAML and HTML5 How you can use the popular KnockoutJS Framework to speed the development of your HTML5 Metro apps. Essential tips, tricks and cautions that will allow you to bring your existing .NET skills to bear quickly in the Windows 8 world. Who this book is for This is a fast-paced guide for developers comfortable with both .NET programming and the fundamentals of Windows 8 development. Table of Contents Setting up Windows 8 Application Project Implementing the View Implementing the Model Implementing the ViewModel HTML5, JavaScript, and Windows 8 Applications View, Model and ViewModel Structures in HTML5 and JavaScript