Many word processing and desktop publishing software products have built-in features to control line breaking rules in those languages.
[1] Line breaking rules for Chinese language have been described in the reference of Office Open XML, Ecma standard.
Regarding prohibited characters, there are some conventions, known as "house rules", which are specific to individual publishers.
For that reason, there are many conventions that are not supported by Western desktop publishing software tools, and that is the main cause of the growing demand of computerized phototypesetting systems.
[clarification needed] Line breaking rules for Korean language have been described in the reference of Office Open XML, Ecma standard.