What even is X (or Twitter)?

I've been going through a lot of my submissions and I seem to come across X a lot. The lit mags I submit to ask for Instagram (which makes the most sense to me) and even more so Twitter, or now X.

I made a poetry account on X probably last year, but it was only today that I ever made my first tweet. (or is it my first X-er? Xweet?) Call me an old soul and sing to me in jazz but I don't have a damned clue on how to use it. Majority of my followers are probably bots that I have to sort through now, but how does one 'market' or 'sell' themselves on this app? Do you just write the randomest thoughts and put it online? Surely, there's some semblance of decorum, but what is it? What is it?

This is probably a question I should have asked Google before writing this. Oh well.