Version History / Major Revisions / Minor Revisions / Publish Versions / Publish Comment / Check In Comment
DIFS can be used to control versioning of import items.
This can be useful if you want to produce a specific version history of a document during import.
If, for example, you are migrating data from a legacy system which had version control and you wished to reproduce that versioning in SharePoint you can do so by adding the files in the correct order, even differentiating between minor and major versions.
You can furthermore influence the publish comment and check in comment that is given to an item.
Please refer to the PDF Documentation for more details.