Finding your Mac OS X version and build information
Summary
Learn about version numbers such as "Version 10.6.8", and build numbers such as "Build 10K540", which appear in the About This Mac window and System Profiler.
Products Affected
Mac OS X 10.0, Mac OS X 10.3, Mac OS X 10.2, Mac OS X 10.1, Mac OS X 10.4, Mac OS X 10.6, Mac OS X 10.5
Discovering your Mac OS