Wikipedia:Non-breaking hyphen

This essay explains use of the non-breaking hyphen character, U+2011, coded by   or. Once displayed in a page, the non-breaking hyphen can be copied into words, or abbreviations, so they will not wrap at the hyphen character, such as an interstate highway symbol, "I‑94", which would always wrap to the next line as a whole word.

Not allowed in calculations
Unlike the ASCII hyphen-minus character "-", the non-breaking hyphen character is typically rejected if used as a negative sign or minus sign in calculations:
 * Using hyphen for minus: {&#123;#expr: 34 - 56}} →
 * Using non-breaking hyphen: {&#123;#expr: 34 ‑ 56}} →
 * Using &minus; for minus: {&#123;#expr: 34 &amp;minus; 56}} →

Similarly, PC pop-up calculators might typically reject the non-breaking hyphen as a character to be ignored, rather than as a form of minus sign.

Judge if worth possible confusion
When using a non-breaking hyphen, care must be taken to ensure whether other editors would understand the unusual nb-hyphen when used in typical text. Confusion can be eliminated by using the HTML character entity  or the template nbh to insert a non-breaking hyphen.

Search will not match
Whether inserted directly or through use of the template, the rendered character, although visually identical, or nearly so (compare:&#8209;-), will not match any search using a standard ASCII hyphen-minus “-”. This is unlike the non-breaking space, whose rendering on the page is indistinguishable from a regular space. This can be fixed by using a regular hyphen and making it and its bordering words non-breaking with the template (shortcut ), for example,. Unfortunately, making only the hyphen nonwrapping has no effect, which precludes redefining the template as. It will work if a hyphen is followed by, but this character fails to render as zero width as it is supposed to when using the Wikipedia app (only tested on Android) (example: xxx-&#x2060;xxx). This can be fixed by enclosing it in  (example: xxx- &#x2060; xxx). Another solution is to follow a hyphen with in its deprecated (since Unicode 3.2) use as. Also usable following a hyphen are  and. All of these satisfy the following three criteria: However, none of these can be used inside wikilinks interchangeably with a standard hyphen. While  links to a standard space, e.g.,   links to J.R.R. Tolkien, both  and  are not invisible, I-& and I-&, while anything with  in it is not recognized as a wikilink, e.g., I-  94. Thus must be used outside a non-piped link:   → I-94. If only part of the link text is to be made non-wrapping then a piped link must be used:  →  route I-94.
 * They prevent post-hyphen breaks.
 * Nothing shows on the page.
 * They are “invisible” to searches.