In the Introduction, we talked about some of the benefits of the functional style when it comes to writing applications. Of course, you can’t learn a language simply by reading about it. To really get a feel for it you have to write some code yourself.
In this chapter we’ll cover how to develop a simple guestbook application that allows users to leave messages for each other. We’ll see the basic structure of a web application as well as the tools necessary for effective Clojure development. If you’re new to Clojure, I recommend taking a look at Appendix 2, Clojure Primer, for a crash course on the basic concepts and syntax.