If an error occurs while installing an update or upgrade, learn how to resolve installation issues. If you downloaded any apps from the App Store, use the App Store to get updates for those apps. When Software Update says that your Mac is up to date, then macOS and all of the apps it installs are up to date, including Safari, Messages, Mail, Music, Photos, FaceTime, and Calendar. Software Update shows only upgrades that are compatible with your Mac.

Upgrade Now installs a major new version with a new name, such as macOS Monterey.

Update Now installs the latest updates for the currently installed version, such as an update from macOS Big Sur 11.5 to macOS Big Sur 11.6.

If your System Preferences doesn't include Software Update, learn how to upgrade to macOS Monterey or upgrade to an older macOS, and use the Updates tab of the App Store app to get app updates. The 10.6.8 update is recommended for all users running Mac OS X Snow Leopard and includes general operating system fixes that enhance the stability, compatibility, and security of your Mac, including fixes that: Enhance the Mac App Store to get your Mac ready to upgrade to Mac OS X Lion.

In the System Preferences window, click Software Update.

From the Apple menu  in the corner of your screen, choose System Preferences.

Then follow these steps to find and install any available software updates or upgrades. The update offers a number of fixes implemented since. Before you get started, it's a good idea to back up your Mac. As hinted at earlier this week, Apple has now released Mac OS X 10.6.8, the eighth maintenance update for Snow Leopard, via Software Update.

Mac os 10.6.8 software update