Javascript is used to make our webpages be more interactive. The downside is that javascript is more complicated than HTML and CSS. We won't learn to program in javascript. Instead, we'll just copy and paste other people's javascript into our own webpages.
There are many websites that have useful snippets of javascript. For example, checkout this webpage: http://www.javascriptkit.com/cutpastejava.shtml . Take two of these javascript snippets that you think look cool, and add them into your webpage.