The recent release of Mozilla Firefox 3.5 seems to have sparked a great deal of discussion about what codecs browsers should support with the newly added
<video> element that was introduced in HTML5.
The believe behind the video element is that video has become so fundamental to the Web that it no longer makes sense to require users to install plug-ins such as Flash or Silverlight in order to watch files. The video element allows for sub elements such as a link to a file that the browser will play if it knows how to play it. It allows you to place other content inside of the tag as a fall back in case nothing can play it, or the browser does not support the video tag to begin with. This means that you could embed Flash (or Silverlight) to play the video if the video tag as a fallback, and barring that you can reference just the little bit more.
The OGG Theora codec is a royalty-free codec, while H.264 (as seen in mp4) is a proprietary codec that offers a higher quality video at a lower bitrate than OGG. Opera and Mozilla are hesitant about supporting H.264 due to licensing and distribution issues, while Apple does not seem to be interested in implementing OGG claiming they are worried concerned about patents. Google (who owns YouTube, which serves out files using H.264, but no OGG) actually supports both file formats in Google Chrome. Microsoft’s recently released IE8 has no support for the video element.
To help keep things clear, here is a Venn diagram. 🙂