The window manager is the most important part of the Linux desktop environment. It defines how your windows look, how they behave, how applications are launched, and how they're closed.
In many cases, window managers have evolved into complete desktop environments, helping with file management, configuration editing and computer management. They're at the very heart of your interaction with the system, but their best feature is that they're swappable, which sets Linux apart from both Windows and OS X.
With Windows you're stuck with, well, Windows. With Linux, you have a choice. And whether you have a preference for a 'do everything' approach, or a 'do nothing at all' one, there's a window manager made for you.
Gnome is the first example of a window manager that's grown into a complete desktop environment. There's also a very good reason why Gnome has become the default desktop environment for the most popular Linux distributions, including Ubuntu and Fedora – it's because it's simple, concise and starting to look rather beautiful.
Taking many cues from OS X, most functions can be reached in one or two clicks, and its designers have reduced screen clutter and superfluous options.
There's an excellent network manager that can help you navigate even the most wayward wireless networks and inconsistent wired ones, while the new on-screen notification system – along with Empathy's support for Twitter, IM and Facebook – mean you have a full screen to fill with your own applications.
Thanks to applications such as Firefox, Chrome and Gimp using the same graphics toolkit as Gnome, many of the most popular Linux applications will feel better integrated with the desktop.
Gnome's great adversary is KDE, a feature behemoth. It's easy to use, but its many and varied options can drown the unwary. That's not to say it's unapproachable, though.
The new window-snapping feature of the latest versions can emulate all the new snapping functions from Windows, and there's integrated support for desktop and panel widgets, nicknamed Plasmoids. These can be dragged and dropped from a small cashew symbol that sits on the top right of your desktop window.
Many of KDE's community-developed features can be downloaded in-line using the 'Get New Stuff' feature of many configuration panels. This means KDE users are always experimenting, and always changing the appearance of their desktops. This can create problems, and recent versions of KDE are somewhat unstable.
KDE is the desktop to choose if you like eye candy, though. It integrates many of the visual effects that have made Linux famous, including the desktop cube, sliding spaces, wobbly windows, drop shadows and hardware zoom.
The new 'Activity' feature means you can restrict visual elements to a specific task, such as 'Office' or 'Downtime', shifting between them as you would a virtual desktop.
Despite being marketed as a lightweight alternative to the likes of Gnome and KDE, you won't find any obvious functionality missing from XFCE: its configuration panels are comprehensive, and the flexibility in the window decoration design is also impressive. You can ape the look of many other popular window managers, as well as creating a custom layout.
There's an integrated file manager called Thunar, a text editor called Mousepad and a custom CD/DVD burning tool, calendar and image viewer. But the key reason to run XFCE is for its speed.
For a fully featured window manager, it still has a low set of requirements, and is ideal for older hardware and netbooks.
4. Enlightenment (E17)
Enlightenment is more than a simple window manager, and less than a full-blown desktop environment. It calls itself a 'desktop shell' and attempts to make all your desktop tasks easily and quickly achievable.
It's also the first of these environments that you're unlikely to find pre-packaged for your distribution. As a result, the easiest way to try it out is to download and run Elive, a Debian-based distribution built specifically to showcase Enlightenment's capabilities.
Elive's Enlightenment looks fantastic. There are deep drop shadows and a dynamically scaling toolbar. Everything opens and moves very quickly. Elive has also pulled applications in from other desktops, such as the file manager from XFCE and Debian's older version of the Firefox web browser.
However, there's a problem – if you want to install Elive, you have to make a donation of at least $15, which we feel is just too much.
The 'Lightweight X11 Desktop Environment' is aimed at older hardware, netbooks and low-powered thin clients. It manages this trick while remaining easy to use because a lot of effort has been spent creating the kind of configuration panels you'd expect to see in Gnome and KDE.
There's an Appearances panel, for example, where you can change the look and feel of the desktop, and a Session Settings window that can be used to define what is and isn't launched at startup.
Like many of the smaller desktops, LXDE is usually augmented with various tools and applications from other environments, including both Gnome and XFCE.
The easiest way to get hold of LXDE is to either install Knoppix, or grab the latest LXDE-themed Ubuntu release, called 'Lubuntu'. The latter provides many more user-installable packages and several mainstream applications.
6. Window Maker
Window Maker is an old-school window manager. It hasn't seen a stable release in over five years, but that doesn't mean you should write it off just yet.
It's design was based on NeXT, the desktop that went on to be the foundation to OS X. The desktop panel, for example, is a low-resource alternative to the ones offered by Gnome and KDE, and you can find plenty of tiny panel applications that can make it a very functional part of your screen. These applets may even be compatible with your current panel.
Window Maker's age gives it another advantage – it runs well on hardware from five years ago.
Based on Blackbox, Fluxbox can normally be installed from your distribution's package manager, and the three packages that come by default shed some light on its philosophy – the window manager, a configuration panel and the pager.
The window manager is lighter than most. You won't find many icons in the launch menu, for instance, and the default toolbar at the bottom of the screen is filled with text. This makes it quick, but it will take a while to learn where your applications are hidden.
Despite the graphical brevity, you'll still find many modern window management features. Applications will snap to a screen's borders, for instance, and the left/right cursor keys in the toolbar will quickly skip between the four virtual desktops. If you need something with a little more shine than simple X11, but don't need any guidance, Fluxbox is the window manager for you.
If you're of a certain age, this is pure nostalgia. AmiWM is a window manager that's designed to look and feel like the old Commodore Amiga WorkBench. It apes version 3.x, rather than the earlier 1.x and 2.x releases, and this means the default background colour is slate grey, while the window borders are blue.
You can even slide down the main window to reveal the default X server that's running in the background. Despite looking just like an Amiga, it's actually a very fast and well-behaved window manager.
You can launch all your favourite Linux applications, and even use the 'Execute Command' functions, just like the old Amiga. Any normal Linux application you might be used to will automatically look like it's been transported back to 1988 – except this time, there's memory protection for the multitasking, and hard drives are affordable.
The unique selling point for Sawfish is that it's built using a Lisp-based programming language. If that doesn't scare you off then Sawfish might be for you. It's one of the most user-configurable and quick window managers you can try.
Almost every function has a user-defined keyboard shortcut, and you can change the way it reacts to events within the window manager.
Sawfish was Gnome's window manager before Metacity, and as a result, it doesn't have some fundamental features, like a desktop panel. This means you'll get your hands dirty, both to install and configure it.
It doesn't look too bad, in a Matrix-style, mid-90s kind of way, but if you don't like the look, it's easy to change. Other users have come up with dozens of better examples and the whole project is still being actively developed.
IceWm is based on Motif, the ageing native toolkit for the X Windows system. This is brave when you consider that Motif is part of the reason why many developers have tried so hard to create an improved desktop experience!
However, Motif does have its good points – it features a very clear and concise design, and IceWM borrows from this, adding lots of improvements. You can control everything from the keyboard, there's a taskbar with launch menu, virtual desktops and both Gnome and KDE compatibility.
The theming engine is impressive, and most default installations include so many that IceWM needs an A-Z menu to list them all.
IceWM is still being actively developed, it's a great modern equivalent to the usual suspects, and about as hard to use as Windows 98.
First published in PC Plus Issue 300
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