Essentially the chroma key is a way of placing drawings underneath the players.
So just to make them look a little bit cleaner, a little bit nicer than sitting on top of the video, the way this works in the software, is it is applied automatically, as you may have seen for drawings where it's required, but you can also be quite flexible.
If you select the chroma key element, you've got some options that pop up. Generally, you don't need to play with these too much, but you can adjust these and see the way it changes the way it looks within the software.
The way the chroma key works then is anything below the green bar element in the timeline, will be affected by the chroma key
And then if you have any drawings above the chroma key, won't be affected
If I select the object to the timeline and just use the up and down arrows on my keyboard, I can move it above and below the chroma key.
So depending on how you want your drawings to look and work, this is a nice way to manipulate that making use of our automatic chroma key, and then the ability to add your own chroma key as well.