What does live performance mean?

what does live a performance mean? I think a live performance is when someone or something performs in front or a large or small audience of people, Not in front of a camera and no audio tune
what could go wrong at a live performance? I think someone could get hurt like fall off stage there could also be technical difficulties also the performers could forget the lyrics or stript.
What did you like about this performance? I like the way they were moving singing and dancing all at the same time I also liked the different personalities.

Here is the link to the greatest showman live.
https://www.youtube.com/watch?v=4E5Sc0G7w90