Desktop environments for Linux are not released ready-made. Behind each is a set of assumptions about what a desktop should be, and how users should interact with them. Increasingly, too, each environment has a history -- some of which are many years old.
As you shop around for a desktop, these assumptions are worth taking note of. Often, they can reveal tendencies that you might not discover without several days of probing and working with the desktop.
Here, for example, are the assumptions and intentions behind seven of the most popular Linux desktops today:
Linux Mint introduced the Cinnamon desktop as "The GNOME 3 Replacement," promising ease of use and a desktop based on the features that users wanted.
What this approach means is a classic desktop with a well-rounded set of administrative and configuration tools. Although innovations such as overviews for file and virtual desktop selection are sometimes part of new releases, and Cinnamon is starting to develop a KDE-like set of panel and desktop applets, the desktop's emphasis is usually on tweaks to improve everyday use.
For example, in the latest release, the software updater includes a descriptive Type column, as well as a description of the available kernels designed to make selecting more intelligent than a simply choice of the latest release.
New users should have no trouble using Cinnamon, but I suspect that hands-on users of at least intermediate expertise are more likely to appreciate its careful habit of incremental improvements. More than any of the other major environments today, Cinnamon listens to users and gives them what they want.
Like KDE, GNOME started as a general desktop and encouraged an ecosystem of utilities and applications. That ecosystem is a study in minimalism, suitable for most everyday uses, but occasionally lacking in advanced cases. It is wildly popular, supporting a majority of the desktop environments mentioned here.
The GNOME desktop environment itself is a more mixed story. With the GNOME 3 release series, GNOME discarded the classical desktop model. Instead, it emphasized removing clutter, which the designs defined as desktop and panel options, and other traditional elements, and automated the assignment of applications to virtual workspaces. In most cases, applications open maximized, and working with two applications at once can be awkward until you learn the tricks.
In addition, modern GNOME uses two main overviews: the one in which you work, and the one in which administrative tasks such as launching applications and manually adjusting workspaces are done.
These design elements can be modified by extensions. Use enough of them, and GNOME 3 becomes a classic desktop -- or just about anything else, if you have the patience for experiments that result in what other environments offer upon installation.
As intended, GNOME is most likely to appeal to those who prefer to work on one thing at a time, and without distractions. Phone and tablet users are also more likely to accept the two overview model than those whose main computer is a laptop or workstation. However, many distributions install GNOME with several extensions, so you are not likely to see GNOME as its designers originally wanted.
KDE began as an effort to be all things to all levels of users. Its goal remains unaltered after eighteen years, which is both a strength and a weakness.
On the one hand, you can set up a basic desktop as quickly as with any other environment, yet still find ways to enhance it and your workflow. KDE is especially strong on customization, with features to alter basic window and desktop behaviors that other desktops have never attempted.
Once you have a basic desktop, you can choose to move on to intermediate features such as multiple icon sets or task-oriented desktops, or advanced ones like KRunner, a menu substitute for those who can find their way around KDE blindfolded.
Alternately, you can stay where you are. Unlike GNOME or Unity, KDE makes no assumptions about the best way to work. Instead, it gives you tools to adopt to your purposes or ignore as you think best.
On the other hand, the weakness to this approach is that it can be overwhelming. Newcomers are presented with so many options that, unless they are aware that they can filter out most options from their attention, they are as likely to be intimidated as enticed.
Similarly, KDE applications have a tradition of including every possible feature their users are likely to need. Applications like Amarok, K3B, or digiKam are famous -- and sometimes infamous -- for their completeness. At times, this insistence on including everything leads to disorganization in the menus that can take several releases to correct.
If you customize heavily, prefer to work your way, and like the idea of growing at your own pace, chances are you will feel comfortable in KDE. By contrast, if you prefer simplicity, or only want a desktop for launching apps, then KDE has aspects of nightmare.
LXDE is a lightweight classical desktop -- and saying more beyond that is almost impossible. Its innovations, such as icons to minimize or shade all open windows, are convenient, but decidedly minor. And LXDE lacks a broad ecosystem of apps compared to older environments like GNOME or KDE. Those who want a no-nonsense, reliable desktop they don't have to think about should find it just what they are looking for.
Those who miss GNOME 2 need look no further than MATE. Originally a fork of GNOME 2, MATE remains dedicated to preserving GNOME 2's look and performance. Features may have different names -- for instance, the Nautilus file manager becomes Caja -- but the functionality is virtually identical with the later GNOME 2 releases.
Not that MATE is a fossil, dedicated to resisting change. Rather, it advertises itself as a "continuation" of GNOME 2. It replaces GNOME's classical menu with a windowed menu, and functions such as software installation and updates are constantly being tweaked. However, generally changes are conservative.
If you have used GNOME 2 any time in the last ten years, then MATE should be a comfortable environment for you. In fact, even those for whom MATE is not their first choice are likely to make it their second choice.
Ubuntu's founder Mark Shuttleworth challenged the free software world to produce desktops that rivaled the OS X. His response to his own challenge was Unity, which was developed largely between 2010-12, and continues to be tweaked.
Unity's original design involved a radical simplification of the desktop that eliminated all panel apps except a few indicators, and app icons on the desktop. Further simplification is achieved by making application menus invisible until the cursor moves to them, and by replacing the classic menu with the dash, a display that fills the entire desktop. The taskbar to show open applications was replaced by a discreet set of triangle indicators, and applications open maximized on the desktop.
New Unity users are likely to be puzzled until they explore a bit, clicking and paying attention to mouse-over help. Yet, even so, Unity is probably the simplest of the desktops mentioned here. Casual users who only open one or two applications at a time are likely to find it suitable to their needs but more demanding users are likely to find it too restrictive, and, at times, dedicated to doing things differently simply for the sake of being different.
Note that recent Unity releases have added Internet search in the dash, a move that was both unrequested and contrary to the simplicity that is one of Unity's main design principles. Aside from the privacy issues raised by these Internet searches, their main result is to make finding items on your hard drive unnecessarily difficult. Turning this feature off is likely to make Unity more acceptable -- but even so, many users feel that Unity restrains both their work flow and their customizations so much as to be an annoyance.
Much of the recent work on Unity has involved tweaking it so that Ubuntu users can have much the same desktop regardless of whether they are working on a workstation or a tablet. Assuming that this promise is realized, it may be the main reason for choosing Unity in the future.
For years, Xfce was the third desktop of free software, trailing far behind GNOME and KDE. Today, however, reader polls consistently put it in second behind KDE and well ahead of GNOME.
It's the users, not Xfce, who have changed. Xfce's home page has declared its goals for years: "to be fast and low on system resources, while still being visually appealing and user friendly." This balance of goals has made Xfce a favorite of organizations like Free Geek and Reglue that refurbish aging computers and distribute them to the needy
However, while Xfce accomplishes both its goals extremely well, they are only part of its appeal. Its Thunar file manager with its library of extensions has a cult following, and Xfce frequently runs KDE and GNOME apps better than KDE or GNOME run each other's. If you run mixed applications, Xfce might be exactly the stable base for your system that you've been looking for.
The Diversity to Give You What You Want
Looking at this list, some readers are sure to suggest that having all these desktops are wasteful, that free software would be in a much better position if it only had a single desktop, like Windows or OS X.
They may have a point, so far as efficiency goes. But, from another point of view, the selection is a tribute to diversity and to giving users what they want.
This diversity can be confusing, but fortunately none of the major desktop environments are inarticulate about the ideas behind their design. In fact, all of them are very thorough about carrying out their intents.
Once you know what each desktop environment is trying to accomplish, you should be able to decide which ones are for you without taking the trouble of booting each in a Live DVD. You may still want to try out a few, but at the very least, you can simplify your selection. Given the selection, you should be able to find something that fits your work habits and personal preferences.