Vtwm (the Virtual Tabbed Window Manager) is an X window manager that was developed from the twm codebase. The first release was in 1990, and it is very much an "old school" window manager, lacking desktop environment features. It added features like xpm icons, autoraising of windows, and a virtual desktop; the latter feature is from where the program takes its name. Later additions include playing sounds in response to window manager events, and Motif-style window decorations in place of the "flat," 2D titlebars commonly associated with twm. Vtwm is released under the MIT license.