|Syntax and mark-up|
Elements in DITA are arranged into domains for organisational purposes and technical reasons.
The base DITA elements are grouped into domains. You can see this clearly in the DITA Language Reference.
Different sets of elements are intended for use when documenting different types of things. The software domain, for example, contains the elements designed to semantically describe software characteristics.
The element domains are technically organised into different DTD or XSD schema modules.