DtAIdentifier is a struct that is used internaly as parent class fo all identifiers in DtArchives.
There is three types of identifiers : InstanceID, ArchiveID and ElementID.

Using identifiers

Identifiers can be created using String, Array or int.
Creating from int mean “hashed identifier”.
Creating from string will create an array of one string and use the Array.
Creating from Array will create a path for the identified thing allowing you to create category/subCategory…

Hashed Identifiers

Why

DtArchive internaly use identifiers as hash. It is exposed to you because that allow an easy copy past and use low memory when stored in a variable.

Limitation

Using hashed Identifiers have limitations, each particular type have its own. See at the bottom of these pages for know more : Instances, Archives, Elements.