what is a line editor?

Ive asked a lot of people this question and have never get a straight answer. If you do a web search you will see the same bullshit definition over and over, that it is an editor that only edited one line at a time before the advent of monitors. So can someone tell me exactly what you are physically looking at when using a line editor? If there is no screen what is the text being displayed on?

>TELETYPE, did you get that?? where the fuck do I find a teletype to try a line editor?

You don't need a teletype.  You can just use a regular monitor, just imagine the text is getting spit out of an old daisy wheel printer if you need to.