i3 (window manager)

i3 is a tiling window manager designed for X11, inspired by wmii and written in C. It supports tiling, stacking, and tabbing layouts, which are handled manually. Its configuration is achieved via a plain text file and extending i3 is possible using its Unix domain socket and JSON based IPC interface from many programming languages.

Like wmii, i3 uses a control system very similar to that of vi and Vim. By default, window focus is controlled by what the documentation refers to as the 'Mod1' key (Alt key/Windows key) in addition to the right-hand home row keys (Mod1+J,K,L,Semicolon), while window movement is controlled by the addition of the Shift key (Mod1+Shift+J,K,L,Semicolon).