Xerox Daybreak (a.k.a. Xerox 6085 PCS, Xerox 1186) is a workstation computer marketed by Xerox from 1985 to 1989. It ran the ViewPoint (later GlobalView) GUI and was used extensively throughout Xerox until being replaced by Suns and PCs.
Despite being years ahead of its time it was never a major commercial success. The proprietary closed architecture and Xerox's reluctance to release the Mesa development environment for general use stifled any 3rd party development.
A fully configured 6085 came with an 80MB hard disk, 3.7MB of RAM, a 5¼-inch floppy disk drive, an Ethernet controller, and a PC emulator card containing an 80186 CPU. The basic system came with 1.1MB of RAM and a 10MB hard disk.
Daybreak was the last machine released in the D* (pronounced D-Star) series of machines, at least some of which shared an instruction set architecture designed by Butler Lampson known as Wildflower. Machines in this series included, in order, Dolphin, Dorado, Dicentra, Dandelion, Dandetiger, Daybreak, the never-manufactured Daisy, and "a multiprocessor system used in a high-end printing system".
The Daybreak was sold as a Xerox 1186 workstation when configured as a Lisp machine and as the Xerox 6085 PCS (Professional Computer System) or Viewpoint 6085 PCS (Professional Computer System) when sold as an office workstation running the Viewpoint system (based on the Star software originally developed for the Xerox Star.)