In the following simple solution, I'll show you how to remove the Yahoo Toolbar from Firefox. The Yahoo Toolbar is often unknowingly installed with other software packages. There is nothing wrong with the Yahoo Toolbar, but if you don't use the tools that are offered, you might consider it to be taking up precous space in your browser.
Uninstalling Yahoo Toolbar from Firefox:
Open your Firefox Browser and navigate to Tools > Addons
Locate Yahoo! Toolbar from the list of Add-ons, then click the Uninstall button to remove the Yahoo Toolbar
Restart Firefox and your Yahoo Toolbar should be gone!