Stacking and Tiling Window Managers Terminology
This post compares what we normally refer to as stacking and tiling window managers. And among tiling window managers, what makes them manual or dynamic.
1 Stacking Window Managers
It doesn't occur to us before we get to approach tiling window managers, but most window managers that we're used to are so-called stacking: Mutter for GNOME, KWin for KDE, FVWM, Enlightenment, etc. Literally, managers which typically lay windows on top of each other.
It's when I became more multitasking, locked my screen instead of logging out at night and started piling up hundreds of windows that I realised that a window manager that will too easily allow that your windows be stacked will cause you to lose track of them. I understood then that having them tiled according to a predictable layout instead would be more useful. That's what tiling window managers do.
2 Tiling Window Managers
There seems to be two major classes of tiling window managers: manual ones and dynamic ones. While manual ones leave it more to the user to adjust the layout manually and allows for more flexibility when arranging windows, dynamic ones rely on layouts to automatically organise the windows. I first saw the definition in Arch Linux's Comparison of Tiling Window Managers.
In practice, a questionable belief is that you tend to spend more time arranging windows when using manual tiling window managers and may end up in messy layouts. Conversely you don't waste any time placing windows when using dynamic tiling window managers but occasionally crave for a bit more freedom in organising them. Of course, the world isn't split into fully-manual or fully-dynamic tiling window management: according to the implementation, you can expect the whole spectrum.
3 It's Not All Black and White
Whether I explicitly read it so or was simply mislead by it, Wikipedia's Comparison of window managers once got me to believe that dynamic window managers support both the tiling and stacking paradigm because they gave xmonad, awesome and, more surprisingly, FVWM as examples. It's true that xmonad and awesome can do some stacking and it turns out FVWM can also do some tiling. However, reading the Dynamic window manager article reveals a Wikipedia definition which describes dynamic as specifically being a tiling window manager paradigm after all – nothing to do with stacking – and which relies on layouts rather than the user's freedom.