[sevenseventen]

There are regional ISBN agencies. The US agency, Bowker, assigns ISBN prefixes by publisher, and publishers assign within their prefix as they please. They're supposed to use one ISBN per edition and format, but many publishers use ISBN as a kind of SKU so you can't 100% count on that.

If that sounds sloppy...I went to publishing conferences fairly regularly from the late 90's into the teens, and I never saw a program that didn't have at least one session or panel titled something like "Publishers must improve their metadata practices."

[bambax]

It's exactly like this. Publishers get a range, and do whatever they want with it.

Also, some agencies sell the numbers range to publishers (I believe the US is in that case) and others give them away at no cost (France). As a result, some small publishers get ISBNs from more liberal agencies than their own country: one can never be 100% sure a French ISBN matches a French publisher for example.

It's also possible some publishers re-use old numbers or affix the same number to different releases/editions of a book.

It's a mess.

But a global centralized system would probably be way worse, so we have to live with that mess.

[amelius]

Why not use UUIDs?

People never enter ISBNs manually, anyways. So it might as well be longer string. Or a QR code.

[dwringer]

As someone who's worked in the field of used books, I can say from personal experience that's not quite true. It's pretty common to have to type in an ISBN for a variety of reasons. Many times the barcodes have been covered up or defaced, and many publications don't have barcodes in the first place.

[amelius]

It was true, for sure. But the question is, is it still true?

[bambax]

Schools often ask for a specific edition of a classic book and the only way to be reasonably sure you're buying the correct one is to search by ISBN.

[amelius]

Well, just copy and paste from the email you got from school.

I mean, if IT can do anything, it is to solve this problem.

[greenie_beans]

same

[sevenseventen]

The point is not just to have universally unique identifiers, but to collect common metadata that's associated with the identifiers. Like this:

https://www.bowker.com/siteassets/files/pdf-files/datasubmis...

Since this is the second time I've mentioned Bowker, let me just say that I do not and have never worked for them or with them, although I did meet with their reps several times when I worked in a different part of digital publishing. It's just that they're inescapable when you're talking about ISBNs.

[layer8]

ISBNs contain a check digit, to prevent typos. So you’d have to invent a new format.

[jszymborski]

Sounds a bit like how DOIs are assigned.

[sevenseventen]

or vice versa! Although DOI RA's are organized functionally rather than regionally. CrossRef -- for journal articles -- is by far the largest RA.

DOI's are far, far more centralized in that CrossRef issues many orders of magnitude more DOI's than all of the others.

The cite-and-be-cited-by use case for scholarly articles is way more compelling than any other use case devised for DOI's.