Depending on the context, I definitely think of commits as all three of diff, snapshot, or history. When I'm coding, I think of myself as "authoring a change"

Depending on the context, I definitely think of commits as all three of diff, snapshot, or history. When I'm coding, I think of myself as "authoring a change" and the commit I post for code review, and later rebase, is the change I'm pushing. (but simultaneously the commit I'm developing against is a snapshot!). Once code is pushed, I flip over to "history". At that point, I'm using the commit as an identifier for a release, which generally contains multiple changes. The primary questions at that point are "what's in this release?" and "How does it differ from the previous release?" and mentally I see that as a set of changes rather than a single diff, even though production doesn't care how many commits are in the difference. The unscientific poll excluded "all three". I guess I have to go with "diff" as "most true" but it simply makes no sense when using a commit id to identify what to check out or release.