An extension extends the functionality of Firefox. These are generally downloaded through their secure site, which can be tricky to find the most useful extensions. My goal is to make it easy to find and use the best extensions for Firefox. Extensions can do many things, from installing useful tools to blocking advertisements to adding entertainment.
To get extensions for Firefox, you click on the Tools menu, then click Extensions. This will bring up the extension manager, a simple interface which allows you to manage your extensions. Click on Get More Extensions.