The JooNext Youtube plugin allows you to simply embed youtube video's in your content. Simply add 1 line of text to your article where you want it and your movie will show. 

Install the plugin as you would any other extension. Then go to extensions/plugins and activate it. In the settings, you can set width and height of a movie.

Add the following line to your article where you want your youtube movie to show. We also have a youtube embed module, with more options

What is the Video ID? When you see the Youtube URL like this: 

www.youtube.com/watch?v=HHUE6YBH12I

HHue6Ybh12I is the video ID.