The web is inherently stateless because all web pages are served up using the stateless HTTP (or HTTPS) protocol. That means that there is no protocol-level mechanism that allows a web page to maintain information from one request to the next. Without outside help, web pages cannot maintain information about an application, a user's session, or even about previous requests for the same page.
This chapter shows you how to manage the various types of state that are critical to all web applications: application state, session state, and view state. Code samples are provided with discussion on utilizing all of these state management tools. Creating custom session state providers, as well as other types of providers, is covered in Chapter 29, "Creating Custom ASP.NET Providers."