What ― means
It marks quoted speech in some typographic traditions. Instead of opening quotation marks, text set this way starts each speaker's turn with the bar. Follow your publication's style rather than swapping every quotation mark for ―.
It belongs to the dash family, where each member has its own job: the hyphen joins words, the en dash marks ranges, the em dash sets off interruptions, and the horizontal bar is the one reserved for quotations.
A literary punctuation choice, not an emotional signal.
For interruptions in English prose, use an em dash; ― is not interchangeable.
What it means when someone sends it to you
2 readingsDon't confuse it with
2Questions people ask
1Why does ― show as a box on some devices?
Because that device's fonts have no glyph for it. The character is still correct and still copies correctly — the box is a missing glyph, not a broken character.
How to type ―
―\2015Codes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.

