As well as addressing a serious security flaw, the update, OSX 10.9.2, also brings a number of new features and is available to download now for anyone with an Apple computer running the Mavericks operating system.
The update addresses a critical SSL-related security hole, christened the "goto fail," a potentially devastating flaw that left Mac users' information exposed when on shared networks or accessing wi-fi hotspots. An attacker could intercept sensitive data such as email log-ins or trick a computer into thinking that a fake sign-in page was the real thing and dupe people into revealing user names and passwords.
On Friday Apple pushed out a fix for the flaw for iPhone, iPad and iPod Touch users and it has now also pushed out a fix for its computers.
And if you're using a Mac that runs Mavericks and you use wi-fi or a shared network, the advice is to install it as soon as possible.
Simply go to the Apple menu in the top left-hand corner of the home screen and click on Software Update and follow the steps. However, make sure to run a backup first and remember that operating system updates require a computer restart.
However, if you're out and about and away from a home or office network connection to safely back up and perform the download, it is possible to mitigate the risks in the short term by using the Google Chrome browser when online rather than Safari.
As well as closing the hole, the update also brings the ability to make voice-only FaceTime calls to the desktop and the ability to block iMessages from specific users. It also addresses one or two bugs in Apple's mail client.