A standard copy-and-paste YouTube embed lands on your page as an
<iframe></iframe> which loads a big ol’ pile of other stuff to play that video. But the UX of it is still essentially an image and a play button. Click the play button and the video plays. You can build essentially the same thing with an anchor link wrapping an image!
This is a very clever idea via Arthur Corenzan. Rather than use the default YouTube embed, which adds a crapload of resources to a page whether the user plays the video or not, use the little tiny placeholder webpage that is just an image you can click that is linked to the YouTube embed.
It still behaves essentially exactly the same: click, play video in place.… Read article “Lazy load embedded YouTube videos”