Do I pay for the bandwidth that is used when I present videos on my website?

Since the videos are embedded from a 3rd party service provider like YouTube, you do not use any of your hosting bandwidth at all to show these videos to your visitors. Although it looks like these videos are playing on your website, they are actually super-imposed onto the webpage, so that it only seems that they are part of your website. This way it is possible to play videos to the public, without paying a fortune for the bandwidth that is used in the process.