Edsger Wybe Dijkstra was born in Rotterdam on 11 May 1930. His mother was a mathematician and father
a chemist. In 1956 he graduated from the University of Leiden in mathematics and theoretical physics. In
1959 he received his PhD from the University of Amsterdam for his thesis entitled ‘Communication with an
Automatic Computer’, devoted to a description of the assembly language designed for the first commercial
computer developed in the Netherlands, the X1. It also dealt with the concept of an interrupt, a novelty at
that time. His PhD thesis supervisor was Aad van Wijngaarden.