Number 3 is pretty cool. Mostly because it is a standard, like HTML, CSS and JS (these are 3, too). Have you ever noticed how many times do you knock the door or how many dots do you write when you don't want to finish a sentence? Most of the songs you hear on Spotify use 3-notes chords, too.
I love music. I play guitar since my teens and keep playing almost everyday. I also studied music theory to know how music works, and why a song can make you feel happy or blue. Nowadays, I mostly play 90s covers. Yeah, I'm a Gen Xer. Kowabunga!
What I'm reading? HTTP/2 in Action by Barry Pollard.