This document discusses audio and video support in HTML5. It covers the audio and video elements that allow embedding multimedia content in web pages without requiring plugins. The audio element is used to embed audio files while the video element embeds video files. Both support various attributes to control playback like autoplay, controls, and loop. Common audio and video file formats like MP3, MP4, Ogg and WebM are supported in HTML5. The document provides examples of using the audio and video elements and describes their attributes.