What Does Partial Document Encryption (PDE) Mean?

Partial document encryption is an encryption method wherein different parts of a document are separately encrypted. This is often done for efficiency of retrieval to lower the demands on the computer system in general.

Techopedia Explains Partial Document Encryption (PDE)

The most common type of partial document encryption involves encrypting each separate page or component of a document separately. This is sometimes called “on-demand” encryption. The idea is that, when a certain piece of the document is requested, it goes out encrypted with its own security certificate. This allows administrators to get around the burden of encrypting the entire document based on a request.