Throughout this book, we will use DOM elements to render game elements. Another popular solution would be to use the Canvas element. There are plus and minus points for both technologies and there are a few effects that are simply not possible to produce with only DOM elements.
However, for the beginner, the DOM offers the advantage of being easier to debug, to work on almost all existing browsers (yes, even on Internet Explorer 6), and in most cases to offer reasonable speed for games. The DOM also abstracts the dirty business of having to target individual pixels and tracking which part of the screen has to be redrawn.
Even though Internet Explorer supports most of the features we will see in this book, I would not recommend creating a game that supports it. Indeed, its market share is negligible nowadays (http://www.ie6countdown.com/) and you will encounter some performance issues.
Now from some game terminology, sprites are the moving part of a game. They may be animated...