What is i3wm.org and what is the i3 window manager?

Updated

i3wm.org is the official website for i3, a tiling window manager written from scratch for GNU/Linux and BSD operating systems. It is free and open source software under the BSD license, aimed primarily at advanced users and developers. The site serves as the project's home for downloads, documentation, and demonstration material.

What i3 is

i3 is a tiling window manager — rather than letting windows float and overlap, it arranges them automatically so they fill the screen without gaps or wasted space. The project describes itself as completely written from scratch, with the target platforms being GNU/Linux and BSD.

The stated design goals, as listed on the site, include:

  • Readable, well-documented code — documentation covers how to extend i3 and explains its internal workings, so users can understand the whole process a window manager is responsible for just by reading the source.
  • xcb instead of Xlib — chosen for a cleaner API and better performance in many situations.
  • Correct multi-monitor support — each workspace is assigned to a virtual screen, with support for attaching and detaching monitors (such as projectors) during operation, plus rotated monitors.
  • A tree structure for arranging windows — enabling more flexible layouts than the column-based approach used by other window managers.
  • Modes, like in vim — for example, different keybindings in a "resize" mode than in the default mode.
  • An IPC interface — other programs can subscribe to events and send commands, described as more lightweight than wmii's use of the 9P filesystem, with core functionality not depending on a separate program.
  • UTF-8 clean handling.

On the visual side, the project takes a deliberately minimal stance: simple borders are described as the most decoration wanted, and the team states it is generally happy with the current feature set, focusing on bug fixes and stability rather than new features.

Who it is for

The site states i3 is primarily targeted at advanced users and developers. If you want a window manager that stays out of the way, is keyboard-driven, and whose behavior you can understand and modify from the source, i3 fits that profile. If you prefer a conventional desktop with floating windows and heavy visual decoration, i3's minimal, tiling approach is a different model.

What you can find on i3wm.org

The homepage points to three main entry points:

  • A screencast — to see i3 in action before installing.
  • The User's Guide — the documentation for learning how to use it.
  • Download — the latest version listed on the page is 4.25.1.

Getting started

  1. Watch the screencast to confirm the tiling workflow suits you.
  2. Read the User's Guide to learn the default keybindings and configuration.
  3. Download the latest version (4.25.1 as listed) and install it on GNU/Linux or BSD.

Because i3 is FOSS under the BSD license, you can read, modify, and redistribute the code. The project's emphasis on documented internals means that even users who are not familiar with all of X11's internals are intended to be able to follow how and why things happen.