Could you give me a link related to any of these!? Looks like a random code!

In-ear monitor (https://en.wikipedia.org/wiki/In-ear_monitor), basically a fancy word for earbuds.

In ear monitor, I believe. The "headphones" that some musicians use on stage to hear themselves. I have heard that you can get them custom made to fit your own ears for a perfect fit.

In this context, I’m pretty sure it’s In-Ear-Monitors; or, the headphones that go in your ear.

I’d also disagree that there’s no difference between price/quality of monitors!

In-ear monitors - or - earbuds, which are generally going to be wired if using 'IEM' over 'earbuds'.

In Ear Monitors, basically a earbuds that goes inside you ear