YouTube parameters: encrypted-media; & clipboard-write; means what?

In the embed code?

The definitions of each would be what?

What do they do, what are their purposes?

<iframe width="642" height="361" src="https://www.youtube.com/embed/tSy7rmtHuRA" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

Updated:

I found this one: encrypted-media;

The definition of youtube embed code is : Its an iframe code so that you can share any youtube video code to worldwide any website where the embed code is allowed. Like you are writing an article and you know a related youtube video. Than you will go to the down of the video. Collect the embed code by copy and paste it on a gap of the article. Than you will see the total video in a iframe within the website where the size will 642 x 341 and the article will be nice. Anybody will be able to see the video within your article by a play button press or they will see the video in a new browser or window.

By my sense: encrypted media means: the total video will come to a link code or within an iframe.
Clipboard write: when you are trying to copy a complete code.

Thanks
masudbcl