With the Video Element you can embed video files in your site. For YouTube videos there is an own element, this element is targeted at raw video files (mp4 preferably, out of compatibility reasons).
For video backgrounds (where you want content on top of the video, use the section background properties).
Usage Examples
Tutorial and product videos.
Videos not serving as background.
Hosting your own videos.
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Video Properties
Video: Upload a video (should be an mp4) or insert the URL that points to it. Please mind your website quota and out of performance reasons it should be less then 10 MB. Please make sure you have the permissions to distribute it!
Play in loop: Play the video in a loop.
Auto-play: Should the video start playing once the user opens the page.
Show controls: Should the controls (pause, play..) be visible to the user. This setting is browser dependent.
Everything else, like spacing, is configured with the common general properties.
See it in action
Video Backgrounds (with section settings)
The video background option in sections is an neat alternative.