[Editor's note: This article is part of our series of articles on installing and upgrading to Mavericks.]Before Lion (OS X 10.7) debuted in 2011, installing the latest major version of Mac OS X meant buying a disc and slipping it into your Mac's optical drive. But Lion changed all that by making OS X available for direct download, and Mountain Lion (OS X 10.8) and Mavericks (OS X 10.9) have inherited this distribution method. More specifically, the latest version of OS X is available only as a download from Apple's Mac App Store--and this time around, it's free. This makes it easier and more convenient to upgrade your OS than having to buy and use a DVD or thumb drive, but it also raises a number of questions, and it presents upgrade obstacles for some users. As I've done the past few years, I've compiled this guide to getting and installing Apple's latest OS.Before proceeding, be sure to read m
