Following are examples of HTML5 Video:

In H.264...

<video id="sampleMovie" width="640" height="360" preload controls>
	<source src="HTML5Sample_H264.mov" />
</video>

In Ogg...

<video id="sampleMovie" width="640" height="360" preload controls>
	<source src="HTML5Sample_Ogg.ogv" />
</video>

In WebM...

<video id="sampleMovie" width="640" height="360" preload controls>
	<source src="HTML5Sample_WebM.webm" />
</video>

All 3 videos...

<video id="sampleMovie" width="640" height="360" preload controls>
	<source src="HTML5Sample_H264.mov" type='video/mp4; codecs="avc1.42E01E, mp4a.40.2"' />
	<source src="HTML5Sample_Ogg.ogv" type='video/ogg; codecs="theora, vorbis"' />
	<source src="HTML5Sample_WebM.webm" type='video/webm; codecs="vp8, vorbis"' />
</video>