Xmonad is a dynamically tiling X11 window manager that is written and configured in Haskell. In a normal WM, you spend half your time aligning and searching for windows. xmonad makes work easier, by automating this.
Why should I use xmonad? xmonad is tiling. xmonad automates the common task of arranging windows, so you can concentrate on getting stuff done. xmonad is minimal. out of the box, no window decorations, no status bar, no icon dock. just clean lines and efficiency. xmonad is stable. haskell + smart programming practices guarantee a crash-free experience. xmonad is extensible. it sports a vibrant extension library, including support for window decorations, status bars, and icon docks. xmonad is featureful. core features like per-screen workspaces, true xinerama support and managehooks can't be found in any other wm. xmonad is easy. we work hard to make common configuration tasks one-liners. xmonad is friendly. an active, friendly mailing list and irc channel are waiting to help you get up and running.
Link: https://xmonad.org/