Tour the State of the Desktop
Not so long ago, desktop environments tended to be variations on a dominant theme. Designed to help the user interact with key parts of the operating system, these interfaces featured icons, toolbars, windows, and folders, and required you to click, scroll, or drag-and-drop to get tasks done.
Then the mobile world took off. From touch-enabled Windows 7 to Ubuntu Linux’s Unity to Mac OS X Lion to Windows 8’s Metro, today’s OSs look more and more like their mobile brethren. Most people are already accustomed to one desktop or another, but we rarely see the alternatives side by side. Take a look at some of todays’ key contenders.
Windows 7

Released back in 2009, Windows 7 offers a desktop interface that has become comfortably familiar to roughly one-third of the computing world, behind only Windows XP, according to Net Applications. Though the interface is touch-enabled, most users’ hardware isn’t, so navigating the desktop remains a matter of pointing and clicking, for the vast majority of users.
GNOME 2

For many users of Linux, GNOME 2 is like an old, comfortable shoe. Dating back to 2002, the desktop has undergone many revisions over the years, but today’s version preserves the same basic paradigm as its predecessors for interacting with the operating system. The most recent GNOME 2 release, version 2.32, debuted in September 2010.
Unity

First appearing in the Netbook Edition for Ubuntu 10.10, or (“Maverick Meerkat”), the Unity interface became the default desktop in Ubuntu 11.04 (“Natty Narwhal”). Borrowing heavily from the mobile paradigm, Unity has generated a significant backlash among many longtime Ubuntu Linux users.
GNOME 3

GNOME 3, which launched in April, has been almost as controversial as Ubuntu Linux’s Unity. Like Unity, this desktop environment borrows heavily from the mobile world, and many users aren’t happy about it. Linux Mint, interestingly, recently announced that it plans to take a hybrid approach to GNOME 3 so users can get used to it incrementally, with access to other alternatives along the way.
Mac OS X Lion

With its release of Mac OS X 10.7 (“Lion”) in July, Apple introduced more than 250 new features to its desktop operating system, promising that it would “change the way you use your computer.” Included among the enhancements were multitouch gestures, full-screen apps, and the Mac App Store.
Windows 8 Metro

Previews of Windows 8 reveal that the Metro design style bears a strong resemblance to Windows Phone 7’s style. Apps are represented by large, constantly updating icons; and the traditional desktop interface is just another “app” within the touch-optimized interface. In fact, at least one observer has said that, in this setting, the traditional desktop now looks like “a drunken uncle at an otherwise elegant family wedding.”
KDE

KDE is the default desktop in numerous Linux distributions, including openSUSE, the Kubuntu derivative of Ubuntu, and Mandriva 2011. Many Linux users have long preferred it as an alternative to the GNOME world. Now available for smartphones and mobile devices as well as PCs, the desktop offers a polished look and a more traditional feel than many of today’s mobile-inspired competitors.
Xfce

Used by default in the Xubuntu variant of Ubuntu Linux, Xfce is a lightweight desktop environment designed to be fast and modest in its system resource requirements, yet visually appealing and user friendly. Because Xfce is modular, you can pick and choose from among numerous separately packaged components to create a customized environment.
Enlightenment

Last but not least, Enlightenment 0.17–known commonly as E17–is a highly customizable modular desktop shell that makes a wide array of beautiful themes available to users. Like many other Linux desktops, E17 performs well on older hardware as well as newer machines. It is the default desktop environment in the Bodhi Linux distribution.