Morning, Fiery Pantone:
file info – what's it for?
The purpose of file info is to add metadata fields in FrameMaker, so that each time you create a PDF the data is there. The reason have these fields in Acrobat is because they are searchable fields. As you amass a collection of PDFs you can search any of the metadata fields to locate the exactly file or files you're looking for.
what do people use 'web statement' and 'job reference' for
To the best of my knowledge, there is no Acrobat equivalent for the these two fields, so entering information in them isn't going to do anything in the PDF. I don't know why they are in FrameMaker, so I'd love to hear a specific answer on that myself.
The other item of note is that you can add the metadata in Acrobat directly—which is incredibly time-consuming—unless you use an action, which makes it super quick. I've been in situations where I forgotten to add the metadata to the FrameMaker document but needed it and didn't want to update the Fm docs and then recreate the PDFs.
~Barb
Resources on this topic. These two posts need updating for current versions (on my list!) but the concepts are still valid.
https://www.rockymountaintraining.com/adobe-acrobat-x-adding-description-fields-to-document-properties/
https://www.rockymountaintraining.com/adobe-acrobat-x-adding-description-fields-to-multiple-pdfs/