Schema markup is code that allows search engines to gather more information about the content of your website pages. It was invented specifically to provide better, more detailed search results for users. It tells search engines what your data means, not just what it says.
In regards to video marketing, Schema markup can provide Google with a great amount of detail about videos that are embedded on your site, including name, description, thumbnail URL, content or embed URL, duration, upload date, and more. Name, description, and thumbnail are all required to ensure the maximum possibility of your video being indexed by Google. Either content URL or embed URL are required, but not both. The rest I mentioned are recommended. However, the more detail you can provide Google, the better off you will be.
When implemented correctly, Schema markup can even help index iFrame embedded videos, which are generally not recommended for embedding videos. Check out the description of this video to see links to Google and Schema.org to learn more about implementing Schema markup on your videos!