Sourced from an early postach.io post - http://blog.postach.io/new-embed-support-for-twitter-vimeo-youtube-about-me-and-more

If you're a programmer or web designer, you may use Codepen.io to show of some code examples. Here's how to use it.

Check out this Pen!

view rawcodepen_shortcode_example hosted with ❤ by GitHub

Url takes the pen address when you are in edit mode, so just copy/paste that into url,height is the height in pixels, and the type can be css, js, html, or result.