HTML5 video tags can embed videos without plug-ins and support multiple formats and JavaScript control. The basic structure includes the source tag to specify compatible formats such as mp4 and webm, the controls attribute to add playback controls, the poster to set the cover image, autoplay needs to cooperate with muted to achieve automatic playback, preload optimizes the loading strategy, JS can call play, pause and other methods for dynamic control, and is widely supported by modern browsers.

The HTML5 video tag allows web developers to embed video content directly into web pages without relying on third-party plugins like Flash. It's a native HTML element that browsers can interpret and play automatically, provided the video format is supported.

Basic Structure of the Video Tag

The video element uses a simple syntax. You wrap it around source elements that point to your video files. The browser selects the first compatible format.

Example:

• controls : Adds play, pause, volume, and seek controls.
• width/height : Sets display dimensions.
• source : Specifies multiple video formats for cross-browser compatibility.
• Fallback text: Displayed if the browser doesn't support HTML5 video.

Supported Video Formats

Different browsers support different video codecs. Common formats include:

• MP4 (H.264) : Widely supported (Chrome, Firefox, Safari, Edge).
• WebM : Open format favored by Chrome and Firefox.
• OGG (Theora) : Less common, mainly in older Firefox versions.

Providing at least MP4 and WebM ensures broad compatibility.

Key Attributes

The video tag supports several attributes to control behavior:

• autoplay : Starts playback automatically (often blocked by browser policies).
• muted : Allows autoplay if the video is muted.
• loop : Repeats the video when it ends.
• preload : Hints how the video should be loaded (eg, "metadata", "auto", "none").
• poster : Displays an image while the video loads or before playing.

JavaScript Integration

You can control the video using JavaScript. For example:

This enables dynamic control based on user interaction or events.

Basically, the HTML5 video tag simplifies embedding and managing video, offering flexibility through markup and scripting. Support is strong across modern browsers, making it a reliable standard for web video.

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