It’s super easy to embed videos, images, tweets, audio, and other content into your WordPress site.

The easy embedding feature is mostly powered by oEmbed, a protocol for site A (such as your blog) to ask site B (such as YouTube) for the HTML needed to embed content from site B.

oEmbed was designed to avoid the need to copy and paste HTML from the site hosting the media you wish to embed. It supports videos, images, text, and more.

SDF oEmbed Widget (and oEmbed Builder Module too) are offering Embed Aspect Ratio which is available in 16:9 and 4: 3.
And you’ll get Responsive Embed as it’s creating an intrinsic ratio that will properly scale on any device.