VP8 is a royalty free video compression format (also known as a video codec).
VP8 was open sourced by Google and is being used as the current default implementation of video codec in WebRTC.
VP8 is available in the implementations of Android, Opera and Firefox browsers across all of the platforms that support WebRTC.
While there is still no decision regarding the mandatory to implement video codec in WebRTC, VP8 is the de-facto one used today.
VP8 is said to be on par with H.264.
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