PCF files are "packaged collaboration files" that allow people to share documents, while also preventing people from working on a document if it does not contain the latest updates. Multiple documents can be contained within one PCF file for project collaboration purposes.
When opening a PCF file, the files within the file can be accessed via email or by using the Insight Connect interface. This is how PCF files are edited and viewed by all users working on a project or collaboration. PAINTCAD, a computer-aided drawing application, also uses PCF file extensions. The files help store the program's font images.