CTWM

In Unix computing, CTWM (Claude's Tab Window Manager) is a stacking window manager for the X Window System in the twm family of window managers. It was created in 1992 by Claude Lecommandeur from the source code for twm, which he extended to allow for virtual desktops ("workspaces" in CTWM's terminology.)

Features of the CTWM window manager include:

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