Do a keyword search in this forum on “Canonical documents” there are threads discussed on the Canonical pros and cons etc…
BTW,Canonical docs (IS Documents) are nothing but generic proprietary documents which are internal to the company that interacts with Databases,ERP applications etc…When defining the canonicals keep in mind to define in a generic way with annotations so that most of the applications integrating could use the same variables/fields.
I’m sure this wasn’t the intent, but this statement implies that canonical document types and IS document types are equivalent. They are not. A canonical document type may have an IS document type representation, but not all IS document types are canonical document types. In fact, very few IS document types will represent canonical document types.