OpenLook

OPEN LOOK (sometimes referred to as Open Look) is a graphical user interface (GUI) specification for UNIX workstations. It was originally defined in the late 1980s by Sun Microsystems and AT&T Corporation.

OPEN LOOK was created at a time when there was little or no standardization in Unix graphical user interfaces (GUIs); the X Window System was emerging as the likely de facto standard for Unix graphical displays, but its designers had deliberately chosen not to specify any look and feel guidelines, leaving this up to application and window manager developers. At the same time, there was increasing use of GUIs in non-UNIX operating systems: the Apple Macintosh was released in early 1984, followed by Microsoft Windows 1.0 and Amiga Workbench in 1985.

As AT&T contemplated its next major revision to Unix, which would eventually become SVR4, it was believed by many that in order to remain competitive with other operating systems, Unix should have a standard GUI definition. One other concern of the time was legal exposure surrounding intellectual property: in March 1988, Apple filed a lawsuit against Microsoft, claiming that Microsoft had copied the Macintosh look and feel.

The OPEN LOOK specification was a collaboration between Sun and AT&T, who were then partnering in the development of SVR4. Xerox PARC was also credited for having not only done the pioneering work in the industry for graphical user interfaces, but also for contributing to OPEN LOOK's "design, review, implementation, testing, and refinement". Involving Xerox, including licensing technology from them, was felt to serve as protection from any future legal entanglements.

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