Non-breaking spaces and special characters

Special characters may be inserted into DITA content using Unicode character escapes.

Your authoring tool may allow the insertion of non-breaking spaces between words. Non-breaking spaces are intended for use when the separation of two adjacent words through line wrapping will result in a loss of meaning or legibility. For example, some authors prefer values and their units, such as "12 kg", to be treated as a single word.

Likewise, soft hyphens are intended for use when there is a preferred point for the breaking of a word during line wrapping.

Some mark-up languages support entities, which allow special characters (not included in the standard character set or not associated with keyboard keys) to be defined using a memorable shortcut. For example, HTML has a   entity for non-breaking spaces. Regardless, provided a character is included in the relevant Unicode character set, it can be included in XML-based content using hexadecimal numeric character references, or character escapes.

Although XML supports entities, the DITA standard itself does not define any text entities. Nonetheless, character escapes can be used. The character escapes for commonly used special characters is:
non-breaking space
soft hyphen
micro symbol
division symbol
non-breaking hyphen
en dash
em dash