A hard line break is a line break that is saved explicitly in the text by putting in a line break character, that is not visible to human readers, but will be used by parsers. A human user inserts this invisible character when he hits return. Some software products also might insert hard line breaks when they wrap the line.

Hard wrapping software should not be used to author wiki markup, because it can put characters in text as a first character in a line. Those character then get special meaning in the wiki markup, although the author did not intend it.

If you use hard wrapping software in conjunction with a wiki you should check the inserted wiki text.

Potential problems occur with

* Equal Signs (Headings)
* Number Signs (Numbered Lists)
* Asterisk (Unnumbered Lists)
* Tables (required one line for one row)
* Any text in blog-like linebreaks mode
* Lists (unless [[MultilineListItems]] are accepted)
* ...

== Software that hard wraps the line

* Outlook by default (E-Mail text get's wrapped)
* BBEdit (optional)
* TextWrangler (optional)
* ... (please add more examples here...)

Another example is the line wrapping options in text area fields for browsers (special to Netscape and IE, no HTML standard). [[http://de.selfhtml.org/html/formulare/eingabe.htm#bereiche_umbruch. |Netscape and IE allow hard line breaks like this]]:
{{{
<form action="textarea_wrap.htm">
  <p>soft:<br><textarea name="soft" cols="30" rows="3" wrap="soft"></textarea></p>
  <p>hard:<br><textarea name="hard" cols="30" rows="3" wrap="hard"></textarea></p>
  <p>physical:<br><textarea name="physical" cols="30" rows="3" wrap="physical"></textarea></p>
  <p>virtual:<br><textarea name="virtual" cols="30" rows="3" wrap="virtual"></textarea></p>
  <p>off:<br><textarea name="off" cols="30" rows="3" wrap="off"></textarea></p>
</form>
}}}