Graphic editing help. What do you call this?

[Sly]

I'm trying to learn video editing but I don't know enough terms to put in the search box.

The thing I'm trying to learn is how to track things on video.



I made a green card and tracked the corners, then used it as a mask for some transparency and skewing. Just basic stuff, you can even see the edges so it's not very good either, it's a start tho. But I'd like to know if there are better ways of doing this. Like, is there a pattern i can use on the card that's better than tracking corners? Is it easier to track dots? Crosses? Circles? Is cardboard too flimsy? Should i have used something else to display on the phone? Is there a name or term for those tracking symbols i can google?

Thanks for any keyword suggestions.