Js pop up? comment? dialog? event rollover?

Greetings all,
New user with first post here.
I want a little info box to display at points along the line with more detailed information about the state of the data at that point in time. I have searched and searched the docs. I assume I can’t find it because I don’t know the keywords or matplotlib jargon, but I know it can be done because a similar technology is on every image in the gallery!!! Gallery — Matplotlib 3.4.1 documentation

What do you call this little black box with the white text, and how do I create it. or find it in a tutorial, documentation, or wherever? Thanks!

I think you want mplcursors or something similar?

I agree that you probably want mplcursors – Interactive data selection cursors for Matplotlib — mplcursors 0.4 documentation. But adding in that I think the jargon name for what you want is tooltip

@Ian and @Jody. Thank you, that does look promising!

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