Concrete Abstractions in the User Interface

Randy Smith, Sun Microsystems Laboratories

Seminar on People, Computers, and Design
Stanford University April 7, 1993


I will present some unusual computer user interfaces in which the sense of physical manipulation is pushed to an extreme. One such system, the Alternate Reality Kit (ARK), is a kind of animated interactive world for building simulations. In ARK, everything appears as a physical object with mass and velocity, including normally intangible things such as a compiler or a law of nature. Thus, the user can grab gravity itself, carry it, throw it, or modify it by attaching buttons and sliders. The peculiar combination of concreteness and abstraction made possible by computer-based realities has some interesting ramifications. Examples to be discussed include the issues of use vs. mention and reflection in the user interface. The talk will feature lots of fun videotape, including bits on a multi-user "shared space" version of ARK, and a version of the system in which objects make sound.


Randall B. Smith is a Senior Staff Member of Sun Microsystems Laboratories Inc., where he co-manages the Self language project. He received his PhD in theoretical physics in 1981, from the University of California at San Diego. After a short period teaching physics at U.C. Davis, he became interested in computers as teaching tools, and joined the Atari Research Lab in 1984. A year later Atari Research Lab crumbled, sending the startled Dr. Smith shooting off to Xerox PARC, where he built the Alternate Reality Kit, and co-designed the object-oriented language Self. In 1988 he spent a year in Cambridge England at the Rank-Xerox EuroPARC research facility, where he worked on real-time collaborative systems and the use of sound inthe interface. He joined Sun Microsystem's new research laboratories in 1991.


Titles and abstracts for all years are available by year and by speaker.

For more information about HCI at Stanford see

Overview Degrees Courses Research Faculty FAQ