[haradion]

> The logical model is identical for every source control system.

Most source control systems have some common logical concepts (e.g. files and directories), but there's actually significant divergence between their logical models. For instance:

- Classic Perforce (as opposed to Perforce Streams) has a branching model that's very different from Git's; "branches" are basically just directories, and branching/merging is tracked on a per-file basis rather than a per-commit basis. It also tracks revisions by an incrementing ID rather than hashes. - Darcs and Pijul represent the history of a file as an unordered set of patches; a "branch" is basically just a set of patches to apply to the file's initial (empty) state.

All of that is above the physical state, which also differs:

- Perforce servers track files' revision histories in a directory hierarchy that mirrors the repository's file structure rather than building a pseudo-directory hierarchy over a flat object store. - Fossil stores everything in an SQLite database.

> Is that relevant to something?

Yes. You can use a VCS reasonably effectively if you understand its logical model but not its physical storage model. It doesn't work so well the other way around.