Now that we've got our feet wet building an Express application for Node, let's work on an application that performs a useful function. The application we'll build will keep a list of notes, and will let us explore some aspects of a real application. In this chapter, we'll only build the basic infrastructure of the application, and in the later chapters we'll add features to it, such as using different database engines to store the notes, user authentication, deployment on public servers, and other things.