A book can exist across many systems.
It appears in publisher databases, bookstore catalogues, library systems, academic citations, and online marketplaces. Titles may vary slightly. New editions are released. Publishers change. Platforms appear and disappear.
Without a persistent identifier, these representations would fragment.
The ISBN solves this.
An ISBN is a unique identifier assigned to a specific book edition. It allows every system to refer to the same underlying entity, regardless of where or how it appears.
A bookstore listing, a library record, and an academic citation may all look different. But the ISBN connects them to the same book.
The identifier persists even as platforms change.
Without persistent identity, records fragment.
With persistent identity, continuity persists.
Source International ISBN Agency