This tutorial will make you think step by step how to add a plug-in (Firefox Add-on) to your Mozilla Firefox browser that will allow you to download videos and music from YouTube and similar sites. The add-on that is used is called Video Downloadhelper. This is a trusted author and a trusted download. To begin this tutorial you will first need Mozilla Firefox and flash. This will enable you to go through the video and help ensure that YouTube will play the video you are trying to download.