Essentially Combo Updaters allow for updating a Mac from a prior version of OS X within the same major release, without necessitating the Mac being on the immediately preceding version point release.In other words, it’s a combined update, including all necessary components from prior point releases, even if they are not installed on the target Mac.However, there are a few things we recommend you do first to ensure things go smoothly, we run through these, as well as instructions for downloading and installing the latest version of the Mac OS in this tutorial.We'll also guide you past the potential headaches and any problems you may encounter.
We also cover how to update your Mac with the more minor updates to the operating system that Apple issues throughout the year at the bottom of this article.
You can read all about the latest version of Mac OS, along with details of the latest point updates and any known issues, here: Mac OS Sierra latest news: current version, updates, betas, and new features.
Apple issues a major update to its Mac operating system once a year, previewing it at WWDC in June, and issuing the final version in September, usually.
If it's just an update to the current version of the Mac OS you need to install jump to this section: Install an update to Mac OS If you want to know how to update your apps on your Mac, read this: How to update all your Mac apps.
The first thing you will want to do is find out exactly which version of the Mac operating system to install and make sure that there is no reason not to install it.