It is safe to say Bill English is the first person to ever use a mouse. In 1963 while Bill was Chief Engineer for Doug Englebart's "Augmented Human Intellect Research Center" at SRI he built the first mouse, based on an idea in Doug's early notes. That same year he designed and ran an experiment which showed the mouse to be the best device for pointing on a computer display. A three-button version of the mouse was quickly developed and reproduced for use in the Center over the next ten years. Bill continued as Assistant Director of the Center until 1971 when he joined PARC. There he managed the Office Systems Research Group and developed the "Hawley" mouse that was used with the PARC Video Terminal System and early Altos.
In 1989, after several international assignments, Bill left Xerox to join Sun Microsystems as Director of Internationalization. He is now retired and consults occasionally on patent issues related to the mouse and early computer systems.