He is a professor of Computer Science at the University of California at Berkeley. He is also the chief technology officer and cofounder of NetRaker. He received his B.S. in Electrical Engineering and Computer Science from Berkeley in 1990 and his M.S. and Ph.D. from Carnegie Mellon University in 1993 and 1996, respectively. His Ph.D.dissertation was the first to demonstrate the use of sketching in user interface design tools. He has published extensively in the area of human/computer interaction, including articles on user interface designand evaluation tools, gesture recognition, pen-based user interfaces, mobile computing, and visual languages. He has also consulted for anumber of Silicon Valley companies.