Paul Graham most recently worked for Yahoo! Inc. Before that he was president of Viaweb, which became Yahoo! Store when Viaweb was acquired by Yahoo! in the summer of 1998. Paul is the author of On Lisp (Prentice Hall, 1993) and ANSI Common Lisp (Prentice Hall, 1995), now the standard college text. He has worked as a consultant to the US Department of Energy, DuPont, and Interleaf. He has an AB from Cornell and a PhD in Computer Science from Harvard.