The easiest way to download and install the latest Apple OS X 10.9 Mavericks OS upgrade is to simply visit the Mac Appstore from your Mac and click upgrade, however if you want to perform a clean installation (format the old setup and install fresh) you will need to create a bootable removable disk drive as shown ahead.

We will be using a simple to use GUI application named DiskMaker X to build a bootable disk drive from Mac OS X installation application downloaded from Apple Macstore (or any other source). As soon as you launch DiskMaker X, the application automatically finds the OS X Install program and proposes to build a DVD or create a bootable install disk as instructed below.

Apple OS X 10.9 Mavericks is finally out now, and surprisingly unlike previous paid upgrades is absolutely free to upgrade this time. The tenth major release of Apple OS X, the desktop and server operating system for Mac computers is now available as a free update through the Mac App Store. Compatible with iMac (Mid 2007 or newer), MacBook (Late 2008 Aluminium, or Early 2009 or newer), MacBook Pro (Mid/Late 2007 or newer), MacBook Air (Late 2008 or newer), Mac mini (Early 2009 or newer), Mac Pro (Early 2008 or newer) and Xserve (Early 2009) the release brings 200+ new features to users. OS X Mavericks brings Maps and iBooks to the Mac, introduces Finder Tabs and Tags, enhances multidisplay support, and includes an all-new version of Safari. The latest release of the world’s most advanced desktop operating system also adds new core technologies that deliver breakthrough power efficiency and responsiveness. While the most recommended and easy method to download and install the new OS is via Apple Mac Appstore, for user's have limited/unreliable internet connectivity unofficial direct download of "Apple OS X 10.9" are posted at the end of this post.

The upcoming major upgrade to the OS X desktop operating-system from Apple for their Mac product lineup named Apple OS X Mavericks got it's sixth "Developer Preview" release. The beta release is now available for download exclusively to registered Apple developers for testing and development purposes only, the beta build is tagged “13A558” for reference. As with every internal/dev-only release their are numerous channels from where non-developers can grab this "EXPERIMENTAL" build (DevUpdateOSX10.9DP6Combo.dmg) as also shared below.

Apple recently released their new major update to Mac OS X desktop operating system as "Mac OS X v 10.7 Lion", thankfully if you are on a older Mac OS X and qualify for the free "OS X Lion Up to Date Program" here is how to grab the upgrade to Mac OS X Lion free of cost from "The Mac App Store" worth US$29.99 normally.