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awesome is a dynamic window manager for the X Window System which launched in 2007. It aims to be extremely small and fast, yet extensively customizable and make it possible for the user to productively manage windows with the use of keyboard.
Its development began as a fork of dwm and is developed in the C and Lua programming languages. The latter is also used for configuring and extending the window manager.
SpecsUpdate
Pros
Pro Move workspaces between monitors
In a multi-head setup, you can move an entire workspace (including all its clients) between monitors. It affords enormous flexiblity. I like to run with 10 workspaces, and I can put any workspace on any monitor (using hotkey shortcuts!), allowing me to rearrange my environment to suit whatever my needs/tasks are at the moment.
Pro Application grouping with tags
Awesome's design paradigm is to use tags to group clients (applications) that can then be pulled into a view (workspace); this allows you to view multiple clients at once and to assign or reassign those tags and their related views on the fly.
Contrary to most other window managers, when you view a tag you are not ‘visiting’ a workspace, you are pulling the tagged windows into a single workspace.
Combined with rules in the config.h, this makes for a flexible and responsive way to manage your workflow.
Cons
Con Lua configuration is baroque and fragile
I'm a very experienced programmer and sys admin. I love lots of things about awesome, but have found configuring it on Debian to be so much work that I've given up on it. Contributing to this is the fact that simple tasks like setting backgrounds or key bindings can involve fairly intricate code paths; it's hard to tell which of the lua config files on my system are being loaded or not, and how they interact; it's hard to tell when there are errors in the running config file or where they are; debian uses config libraries like beautiful by default, and those interact with solutions I find on the web in complicated ways that require a lot of effort to disentangle.
Con Resize buggy
That's more for personal experience with Awesome that some Windows are not re-sized properly.
Issues include: Terminals not re-sized to bottom of the screen to re-sizing back to 1 pixel size, cannot move windows, cannot re-size panes or doesn't re-size contained window properly (observed with Hangouts Chrome extension for example).
Con Difficult to google for solutions to problems
Awesome is a very common word, searching for solutions to problems using Google is very time consuming as a lot of chaff has to be sifted through.
Recommendations
Comments
Flagged Pros + Cons
Con You should have some skills to configure it
Awesome, like most window managers, is targeted at advanced users. Though is has sane defaults and easy to read documentation, it is still a far jump from the more common graphical UIs found in computing.
Pro Xinerama support
Awesome has real multi-head support via XRandR/Xinerama, with per-screen desktops.