A file says what it is once, for the whole file: one title, one author, one date. That is plenty for a letter. It says nothing useful about anything bound out of pieces — a register made of two sittings held years apart, or a scan whose photograph belongs to somebody other than whoever holds the paper. Anyone digitising an old collection meets this on the first box.
Here each of the two pages carries a record of its own: what it is, whose hand wrote it, the day it was written. The photograph carries one as well, because the rights on a photograph are not the rights on the document carrying it, and losing that distinction is how an archive ends up unable to say what it may publish. Each typed-up transcription is attached to the page it transcribes rather than to the file at large — which only became possible with PDF 2.0, so the file says 2.0 openly instead of being moved up a version behind your back.
Nothing is left out and nothing is simplified: this is the program exactly as it runs, for the developer who uses this library. The third is the description itself: a plain list of what the page has to say, which is what the service is sent.
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The document is lighter than it was, and every page still looks exactly the same. See this document's row in the table of every example.
Three rulers — centimetres, inches and points — on a page that tells whatever prints it to put it out at exactly the size it was drawn, and to offer nothing else. Lay a tape measure on the printed sheet and you can check for yourself.
A records office's reference, the department it came from, the date until which the document must be kept and its classification, carried inside a file an archive still accepts. No archiving rule knows what a keep-until date is, so each entry carries a description of itself, and that description is what makes a checker accept a fact you alone invented.
Every line of the note carries the order it was picked for, the article code and the shelf it came off, and prints none of them. The place where the driver signs carries the round and the van, and one beside the fold tick carries nothing but its own place.
Two pages carrying a copy of themselves that nobody sees: this is a heading, this is a table, and this is the order to read them in. Software reading the document aloud follows that instead of the order the marks were drawn in, and skips the running head. On the page, nothing looks any different.
A parts list whose first column is a picture rather than a word. Each picture carries the sentence somebody hears in its place, so nothing in the list is lost on a reader who cannot see it. On the page, the pictures are simply pictures.
The electronic invoice French law has required since September 2026: one file, a page a person reads and the same invoice inside it as XML. Nothing to reconcile afterwards, because there is only ever one invoice.