Software update, upgrade--what's the difference?
Find out the differences between an Apple software update and an upgrade.
An Apple "software upgrade" means a major, standalone version of a software product. Such products are usually something you purchase. OS X upgrades are sometimes also called "reference releases."
For example, OS X Mountain Lion is an upgrade that is available from the Mac App Store.
A "software update" updates a major (reference release) version of software, but does not upgrade it to the next major version (if one exists). Software updates are made available via download from the Software Update application (or the Mac App Store in Mountain Lion) in OS X and typically provide fixes that enhance the stability, compatibility, and security of your Mac. For example, Apple provided the OS X v10.7.4 Update as a software update to OS X Lion v10.7.
- A software update is usually downloadable free of charge; a software upgrade usually is not.
- A software upgrade usually increments the first "dot" number of a product (for example OS X Lion v10.7, Mac OS X Snow Leopard v10.6); a downloadable software update usually increments second "dot" number (for example, Mac OS X v10.7.4).