• Improves compatibility with certain third-party USB audio devices
• Improves VoiceOver navigation when viewing PDF documents in Preview
• Improves compatibility of Braille displays with Mail

The update also “improves the stability, compatibility and security of your Mac,” explains Apple.

You can install this update by going to the Mac App Store and clicking on the Updates tab. This update requires a restart. You may want to wait until the end of the day to install this, if you’re wary about bugs and such.