Sir Maurice Vincent Wilkes (26 June 1913 – 29 November 2010) was an English computer scientist who designed and helped build the Electronic Delay Storage Automatic Calculator (EDSAC), one of the earliest computers that use stored programs. He also invented microprogramming, a method that uses stored-program logic to control the circuits of a computer’s central processing unit. In 1967, he received the ACM Turing Award. At the time of his death, Wilkes was a retired professor at the University of Cambridge.

Early life, education, and military service

Wilkes was born in Dudley, Worcestershire, England, as the only child of Ellen (Helen), née Malone (1885–1968), and Vincent Joseph Wilkes (1887–1971), who worked as an accounts clerk for the estate of the Earl of Dudley. He lived in Stourbridge, West Midlands, and attended King Edward VI College, Stourbridge, for his education. During his school years, he was introduced to amateur radio by his chemistry teacher.

He studied mathematics at St John's College, Cambridge, from 1931 to 1934. In 1936, he completed his PhD in physics, focusing on how very long radio waves travel through the ionosphere. He held a junior teaching position at the University of Cambridge, where he helped create a computing laboratory. During World War II, he was called to serve in the military and worked on radar technology at the Telecommunications Research Establishment (TRE) and in operational research.

Research and career

In 1945, Wilkes became the second director of the University of Cambridge Mathematical Laboratory, which later became known as the Computer Laboratory.

The Cambridge laboratory had many different computing devices, including a differential analyser. One day, Leslie Comrie visited Wilkes and gave him a copy of John von Neumann’s prepress description of the EDVAC, a computer being built by Presper Eckert and John Mauchly at the Moore School of Electrical Engineering. Wilkes had to read it overnight because he had to return it, and there were no photocopying machines at the time. He realized the document described the logical design of future computers and decided he wanted to help build such machines. In August 1946, Wilkes traveled by ship to the United States to join the Moore School Lectures. He was only able to attend the final two weeks due to travel delays. During the five-day return trip to England, Wilkes sketched the logical structure of the machine that would later become EDSAC.

Because his laboratory had its own funding, Wilkes began work on a small practical computer, EDSAC (short for "Electronic Delay Storage Automatic Calculator"), as soon as he returned to Cambridge. He focused on making a computer available to the university rather than inventing a more advanced one. He used only proven methods to build each part of the computer. The resulting machine was slower and smaller than other planned computers of the time. However, it was the second practical stored-program computer to be completed and successfully operated in May 1949, more than a year before the larger EDVAC. In 1950, Wilkes and David Wheeler used EDSAC to solve a differential equation related to gene frequencies in a paper by Ronald Fisher. This was the first time a computer was used to solve a problem in biology.

In 1951, Wilkes developed the idea of microprogramming after realizing the central processing unit (CPU) of a computer could be controlled by a small, specialized program stored in high-speed ROM. This idea made CPU development easier. Microprogramming was first described at the University of Manchester Computer Inaugural Conference in 1951 and later published in IEEE Spectrum in 1955. It was first implemented in EDSAC 2, which used identical "bit slices" to simplify design. Replaceable tube assemblies were used for each bit of the processor. The next computer built by Wilkes’ laboratory was the Titan, a joint project with Ferranti Ltd starting in 1963. The Titan supported the UK’s first time-sharing system, inspired by CTSS, and provided access to computing resources, including time-shared graphics systems for mechanical CAD.

A key feature of the Titan’s operating system was its ability to control access based on the identity of the program, rather than the user. It introduced a password encryption system later used in Unix. Its programming system also had an early version control system.

Wilkes is credited with creating symbolic labels, macros, and subroutine libraries. These innovations made programming easier and helped develop high-level programming languages. Later, he worked on an early time-sharing system (now called a multi-user operating system) and distributed computing. In the late 1960s, he became interested in capability-based computing, and the laboratory built a unique computer called the Cambridge CAP.

In 1974, Wilkes studied a Swiss data network (at Hasler AG) that used a ring topology to manage time on the network. His laboratory first used a prototype to share peripherals. Later, commercial partnerships formed, and similar technology became widely used in the UK.

Wilkes received many honors, including being made a Knight Bachelor, a Distinguished Fellow of the British Computer Society, a Fellow of the Royal Academy of Engineering, and a Fellow of the Royal Society. He was a founder of the British Computer Society (BCS) and its first president from 1957 to 1960. He received the Turing Award in 1967 for building the EDSAC, the first computer with an internally stored program. The EDSAC used a mercury delay-line memory. He also co-authored a book in 1951 that introduced program libraries. In 1968, he received the Harry H. Goode Memorial Award for his contributions to computer engineering and software, as well as his work in professional societies.

In 1972, Wilkes was awarded an honorary Doctor of Science degree by Newcastle University. In 1980, he retired from his professorships and joined Digital Equipment Corporation in Massachusetts, US.

Wilkes received the Faraday Medal from the Institution of Electrical Engineers in 1981. The Maurice Wilkes Award, given annually for outstanding contributions to computer architecture by young professionals, is named after him. In 1986, he joined Olivetti’s Research Strategy Board. In 1987, he received an honorary Doctor of Science degree from the University of Bath. In 1993, Cambridge University awarded him an honorary Doctor of Science degree. In 1994, he became a Fellow of the Association for Computing Machinery. He received the Mountbatten Medal in 1997 and gave the inaugural Pinkerton Lecture in 2000. He was knighted in the 2000 New Year Honours List. In 2001, he was inducted as a Fellow of the Computer History Museum for his contributions to computer technology, including early machine design, microprogramming, and the Cambridge Ring network. In 2002, he returned to the University of Cambridge as an emeritus professor.

Wilkes wrote several books, including:
– Oscillations of the Earth's Atmosphere (1949), Cambridge University Press
– Preparation of Programs for an Electronic Digital Computer (1951), with D. J. Wheeler and S. Gill, Addison Wesley Press
– Automatic Digital Computers (1956), Methuen Publishing
– A Short Introduction to Numerical Analysis (1966), Cambridge University Press
– Time-sharing Computer Systems (1968), Macdonald
– The Cambridge CAP Computer and its Operating System (1979), with R. M. Needham, Elsevier
– Memoirs of a Computer Pioneer (1985), MIT Press
– Computing Perspectives (1995), Morgan Kaufmann Publishers

Personal life

In 1947, Wilkes married Nina Twyman, a specialist in classical literature. She passed away in 2008, and he passed away in 2010. Wilkes was survived by one son and two daughters.