Magxtopher:
FYI, I moved your posted to the forum about the Beginning JavaScript 3rd edition book.
As to what games can you make with it? Well, the book has an example of a simple game you'll build. More importantly, learning JavaScript will give you a good basis to learn the similar ActionScript language, which you might use in programming Flash games for example.
In itself, you probably won't do much real game programming just with JavaScript.
Jim Minatel
Acquisitions Director
Wiley Technology Publishing
WROX Press
Blog:
http://wroxblog.typepad.com/
Wrox online library:
http://wrox.books24x7.com