For those just starting to build web applications, we thought it useful to provide a high-level overview of how ASP.NET works to service user requests. Web development is a large and diverse topic. However, at its core, it is just Hypertext Markup Language (HTML) web pages pushed to browsers from web servers over Hypertext Transfer Protocol (HTTP) request/response. Understanding these fundamental concepts makes it easier to work with the greater complexities of web development (which we cover throughout this chapter). If you are familiar with writing web applications, we expect you to glance at Figure 17.1 and skip this section.