The videos here are in the patent-free Ogg Theora video format. This format is natively supported by both Mozilla Firefox and Chromium without any "plug-ins" or "extensions" necessary. If you're not already using Firefox (or Chromium) for your Internet surfing, you really should. They're both free downloads.
Additionally, several standalone video players like VLC and MPlayer support Ogg Theora playback. If you're running any GNU/Linux or BSD system, you are already golden. There are also versions for Microsoft Windows and Apple MacOS.
The videos provided here are for informational purposes only. I do not assume any responsibility what-so-ever if you get hurt in any way from following what we do in these videos. Personal safety is your responsibility, so use this information at your own risk!