Before updating to mountain lion
Perhaps one of the most important changes, according to Apple, is one that may not be immediately obvious.
The company says that for many Mac Books, Mavericks offers so many new energy-efficient features that it could add up to an extra hour of battery life.
The Apple Maps app has also been updated to make it easier to search for directions on your Mac and then send them to your i Phone.
In the upper left-hand corner there's a new share button to let you do this. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission.
There's a fresh, new look along with potentially longer battery life.
And along with new features such as i Books, some stalwarts like Safari, Maps and Calendar all get some snazzy improvements.
Before downloading any major update to your Mac operating system, it is very important to back up your data.
But before you hit the download button, there are a few things you might want to know about Mavericks and your own machine.
First, you'll want to check that your Mac or Mac Book is actually compatible.
Chances are that it is, since Apple seems to be trying to make it as widely available as possible.
Still, Apple's official list of machines that can run Mavericks is as follows: i Macs bought as far back as mid-2007; Mac Books as old as the late 2008 aluminum model or newer; Mac Book Pro models from mid- to late 2007 or newer; Mac Book Air models from late 2008 or newer; Mac Mini models from early 2009 or newer; Mac Pro from early 2008 or newer; and Xserve from early 2009.