Anyway, here's a cool video about conlangs, or constructed languages. It focuses on artlangs (languages invented for books or films) such as Elvish (The Lord of the Rings trilogy), Klingon (Star Trek) and Dothraki (the Game of Thrones series).
It would be pretty amazing to have your own language (as long as a few other people spoke it). But a bespoke language also sounds like a lot of work to construct. Fortunately for authors, the Internet is there to help. Thanks to fans, languages like Dothraki that began with just a few thousand words are now complex enough to be spoken.
That means if there's no word for IRREGULAR in Elvish, you might get to be the person who makes one up.