HD stands for High Definition.
For video, high definition means support for higher video resolutions. For TV, HD usually means 1920×1080 pixels, while in video calling, HD usually means 1280×720 pixels.
For voice, high definitions means wideband.
About WebRTC Glossary
The WebRTC Glossary is an ongoing project where users can learn more about WebRTC related terms. It is maintained by Tsahi Levent-Levi of BlogGeek.me.
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