Wilkes is also one of the ``grandparents'' of computing. He was around the day that EDSAC became the world's first opreational general-purpose programmable computer. He is credited with saying that they ``discovered'' debugging that very same day while attempting to execute a simple program for generating a table of prime numbers (see ``The Multics System'' by Elliot I. Organick, The MIT Press 1972, pg. 127).