The ph element is used to enclose a phrase for reuse or conditional processing (for example, when part of a paragraph applies to a particular audience). It can be used by specializations of DITA to create semantic markup for content at the phrase level, which then allows (but does not require) specific processing or formatting.
See appendix for information about this element in OASIS document type shells.
<p>This was not changed. <ph rev="v5r2">This was updated.</ph> This was not.</p>