When seeing the dynamic nature of Google Maps, you might think there is something magical going on under the hood. But there’s really nothing magical about it. It’s just HTML, CSS, and JavaScript working together. The map tiles are images that are loaded in the background with Ajax calls and then inserted into a in the HTML page. As you navigate the map, the API sends information about the new coordinates and zoom levels of the map in Ajax calls that return new images. And that’s it! No magic involved whatsoever.
The API itself basically consists of JavaScript files that contain classes with methods and properties that you can use to tell the map how to behave. Exactly what those classes are and how to use them is the subject of this book.