What do the numbers in a version typically represent (i.e. v1.9.0.1)?

Question

Maybe this is a silly question, but I\'ve always assumed each number delineated by a period represented a single component of the software. If that\'s true, do they ever rep

Answer 1

In the case of a library, the version number tells you about the level of compatibility between two releases, and thus how difficult an upgrade will be.

A bug fix release needs to preserve binary, source, and serialization compatibility.

Minor releases mean different things to different projects, but usually they don't need to preserve source compatibility.

Major version numbers can break all three forms.

I wrote more about the rationale here.