source

The source element allows authors to specify multiple alternative media resources for media elements. It does not represent anything on its own. The src attribute gives the address of the media resource. The value must be a valid non-empty URL potentially surrounded by spaces. This attribute must be present.

<video controls="controls">
 <source src="https://media.w3.org/2010/05/sintel/trailer.mp4"
 type='video/mp4; codecs="avc1 mp4a"/>
 <source src="https://media.w3.org/2010/05/sintel/trailer.ogv"
 type='video/ogg; codecs="theora vorbis"/>
 <p>Your user agent does not support the 5 Video element.</p>
</video>
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