OpenLayers is, at a fundamental level, not doing anything that is conceptually too hard to grasp. It gets map images from a server, and puts them together. From a technical level, however, there is a lot of work going on, and it might seem magical how it all works together so well.

Fortunately, there are many tools to dispel any potential magical thinking we might have and show us how OpenLayers is working behind the scenes. Firebug, a free and open source plugin for Firefox, is one such great tool. Speeding up development time, viewing network communication, and squashing bugs are just a few things that Firebug, and other web development tools, do that make them hard to live without.

To really use OpenLayers effectively and to its full potential, we need to understand how it works. In this chapter, we'll try our best to do just that, by using web development tools to examine OpenLayers' inner workings. By doing so, we'll accomplish two things. First...