There is no hard-and-fast standard, but typically, it is <major release>.<minor release>.<build> . The build number changes daily in a product under development, but few see the light of day, and some minor "releases" never get released either. Every developer has their own standard of what will trigger the next minor and/or major release number.
Major.Minor.Build is correct. The Major number rarely changes. The minor changes every time we kick off a new series of builds for a particular project. The build number changes every time a build is done on our controlled build machine.
Comments
I believe it's typically major.minor.build
~ Eric Medley
--John