https://www.youtube.com/watch?v=LYTK6QicICo
There are all sorts of codes, patterns and puzzles throughout history.
https://fusionanomaly.net/voynichmanuscript.html
https://fusionanomaly.net/agrippa.html
https://fusionanomaly.net/synchronicity.html
https://desertshapes.blogspot.com/search?q=cryptic+notes+and+memes