In this chapter, we looked at declaration files and how to generate our own. We installed the NuGet extension for Visual Studio, allowing us to easily install third-party libraries for applications. Then, we covered some of the more common web application libraries in jQuery and Knockout that can be used to easily create large, dynamic, and interactive applications. Finally, we covered external modules and RequireJS to optimize the loading of our modules. In the next chapter, we will use these new tools to improve both our code and the user experience of the drawing application created in Chapter 5, Creating a Simple Drawing Application.