Soft hyphen

Two alternative ways of using the soft hyphen character for this purpose have emerged, depending on whether the encoded text will be broken into lines by its recipient, or has already been preformatted by its originator.

[1][2][3] The use of SHY characters in text that will be broken into lines by the recipient is the application context considered by the post-1999 HTML and Unicode specifications, as well as some word-processing file formats.

The zero-width space, on the other hand, will not, as it is considered a visible character even if not rendered, thus having its own kerning metrics.

This is the application context originally considered by the EBCDIC and ISO 8859-1 standards and implemented in many VT100 terminal emulators.

An example application that outputs soft hyphens for this reason is the groff text formatter as used on many Unix/Linux systems to display man pages.