This chapter briefly introduced AJAX and DWR. AJAX is a fundamental technology that uses browser-based JavaScript to build Internet applications with better user experience than typical request-response web applications.

DWR is a Java framework for building AJAX applications, and it is targeted mainly at Java developers who don't want to implement the low-level "stuff" that makes AJAX work.

The rest of the book is about DWR features and sample code that can be used in your own projects. The examples provided in the later chapters show some of the common situations in which to use DWR and how to use it.