OpenBox

Openbox is a lightweight, highly configurable window manager for the X Window System. It is designed to be fast and resource-efficient while offering extensive customization options. Openbox began as a fork of Blackbox 0.65.0 and is released under the GNU General Public License (GPL) version 2 or later.

As a stacking window manager, Openbox handles window decorations, placement, focus, and simple window interactions. It supports keyboard and mouse bindings, configurable window placement rules, and the ability to create complex user workflows through scripts and events. Visual appearance is controlled by themes, borders, and shadows. Configuration is primarily done through XML files, notably rc.xml for behavior and keybindings and menu.xml for the application menu; a separate tool, OBConf, provides a graphical interface for common settings. Openbox also supports EWMH/NETWM standards to enable interoperability with other desktop components and panels.

Openbox adheres to standards to enable interoperability with other desktop components and panels. It can serve as the sole window manager in a minimal setup or be embedded as the WM component of a larger desktop environment. It is commonly used with lightweight desktops such as LXDE and, in some configurations, LXQt, but it remains usable in a wide range of Linux distributions.

Its low memory footprint and fast startup make it popular on older hardware and minimalist distributions. Development focuses on stability, standards compliance, and extensibility through external scripts and toolchains rather than feature-heavy changes.

Related topics include LXDE, LXQt, and Blackbox.