Bill Atkinson, the Apple computer designer, dies at 74

ATKINSON, THE Apple computer designer who created software that enabled the transformative visual approach pioneered by the company's Lisa and Macintosh computers, making the machines accessible to millions of users without specialized skills, died on Thursday at his home in Portola Valley, California, in the San Francisco Bay Area. He was 74. In a Facebook post, his family said the cause was pancreatic cancer.

- JOHN MARKOFF

It was Atkinson who programmed QuickDraw, a foundational software layer used for both the Lisa and Macintosh computers; composed of a library of small programs, it made it possible to display images, text and images on the screen efficiently.

The QuickDraw programs were embedded in the computers' hardware, providing an instinctive graphical user interface that presented a simulated "desktop," displaying icons of folders, files and applications. Atkinson is credited with inventing many of the key aspects of graphical computing, such as "pull down" menus and the "double-click" gesture, which allows users to open files, folders and applications by clicking a mouse button twice in succession.

Before the Macintosh was introduced in January 1984, most personal computers were text-oriented; graphics were not an integrated function of the machines. And computer mice and pointing devices were not readily available; software programs were instead controlled by typing arcane commands.