In a Certified PDF workflow, a PDF document can go through various editing sessions, done by various users. A Certified PDF document can “remember” all the changes that were made during a given session and can store the information about these changes per session (“incrementally”) as you save your PDF document.
This way of managing and saving changes has a big advantage: You know exactly which changes have been made in which session and by whom. Moreover, these changes can be presented to you in the form of a “snapshot”: a view of the status of the PDF document at the time it was saved at the end of a session.
And you can do even more: You cannot only view the state of the PDF document in a given previous editing session, you can also save this snapshot as a separate PDF document. This is called the roll-back mechanism. When editing PDF documents, you may have experienced “one-change-too-far” situations, in which you made a change, got an undesired result but also saved the PDF document. No problem in a Certified PDF workflow: you can revert to any previously saved state of a PDF document, provided that you save your Certified PDF document using CTRL+Shift+s).
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