IBM wanted a standard way to interact with text-based user interface software, whether the screen was a dumb terminal connected to a mainframe or a PS/2 with VGA graphics.
Its aim was in part to bring about harmony among DOS applications, which until then had independently implemented different user interfaces.
[4] When it was first written, the Mac was new, and graphical user interface (GUI) software was a novelty, so Apple took great pains to ensure that programs would conform to a single shared look and feel.
[citation needed] CUA had a similar aim, but it faced the more difficult task of trying to impose this retroactively on an existing, thriving but chaotic industry, with the much more ambitious goal of unifying all UI, from personal computers to minicomputers to mainframes; and supporting both character and GUI modes, and both batch and interactive designs.
Some of these standards can be seen in the operation of Windows itself and DOS-based applications like the MS-DOS 5 full-screen text editor edit.com.
The current major environments, GNOME and KDE, also feature extensive CUA compatibility.
The subset of CUA implemented in Microsoft Windows or OSF/Motif is generally considered a de facto standard to be followed by any new Unix GUI environment.