Unique page ID
In web technology, a unique page ID is a number assigned to a page in order to address it uniquely. This makes it possible to change the title of a page at any time, while the links to this page do not have to be changed.
IDs in MediaWiki
MediaWiki works in the standard without a single page ID. Here the title is unique and can only be assigned once. This prevents the parallel existence of identical page titles. The users should gather their knowledge to a term in one place.
However, the Wiki internally carries a numeric ID, which is not displayed. In order to make this ID visible and usable, an extension must be programmed.
MediaWiki also has the function permanent links in the standard version, with which you can link to a specific article version. It is also possible to manually assign a document number to an article. So that this can be read and used, one can work with semantic functions.