If you've been following the YouTube Channel known as H3H3 you probably already know about their victory defense of a lawsuit. But if not, and are a content creator or plan to in the future, you might run into the concept of Fair Use. Fair Use has to do with copyright, and the limits of how to use someone else's work for editorial or commentary purpose.
"In its most general sense, a fair use is any copying of copyrighted material done for a limited and “transformative” purpose, such as to comment upon, criticize, or parody a copyrighted work."
You can find out more about Fair Use from this Standford website
Basically, the duo of Ethan and Hila, had a lawsuit filed against them by another YouTuber, who said their use of his content in their video was a copyright violation in addition to other claims. After about 20 months they have gotten a summary judgement to dismiss the entire case in their favor. The resulting opinion written by the judge helps to strengthen Fair Use.