are you trying to write on markdown? 
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Underscores have been used for emphasis in emails etc. long before there was markdown.
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IIRC this goes back to troff at least.
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Doesn't seem like it's used in troff, but I've never directly used it. It's probably been around as long as computer-typing, as "underline"
End of conversation
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The first 18 years are the hardest.
Thanks. Twitter will use this to make your timeline better. UndoUndo
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