|The DITA documentation process|
To make it easier for authors to choose semantic mark-up elements, it is possible to reduce the number of elements available for selection. This restriction can be managed by an authoring tool, or through the constraints mechanism introduced in DITA 1.2.
Some authoring teams choose to restrict the DITA elements they allow their authors to use. This might be an informal restriction ("don't do it or else!"), or a formal restriction (by software).
Some DITA authoring tools provide the facility to restrict or limit the elements displayed in the authoring interface. The restrictions are usually managed on the basis of element mark-up domains, which are groups of elements intended for common subject matter.
Example of an authoring tool dialog box for hiding DITA mark-up domains
The constraints mechanism introduced in DITA 1.2 provides a standard for creating constrained information types, which can be used to make the element choices for the author simpler.