Computer Science History

Kathleen Booth, the inventor of assembly language, Dead at 100

Obit in the Reg:

Professor Kathleen Booth, one of the last of the early British computing pioneers, has died. She was 100.


As well as building the hardware for the first machines, she wrote all the software for the ARC2 and SEC machines, in the process inventing what she called Contracted Notation. This language, through evolution and contributions by others, is today known as assembly language.

She also co-founded the Computer Science Department of Birkbeck University of London with her future husband:

From the start, Kathleen Booth was closely involved in the building and testing of the computers that Andrew Booth designed. Getting these early machines to work involved a combination of testing the electronics and then checking that the programs executed correctly. In 1953, they co-authored their best known book entitled “Automatic Digital Calculators” which ran to three editions. As part of her software development work, Kathleen developed a very early assembly language for their computers and in 1958 she published a book on software entitled “Programming for an Automatic Digital Calculator”.

Their best known machine APEC (All Purpose Electronic Computer) was designed in 1949. In 1951, BTM used its hardware circuits as the basis of the design of their HEC1 computer which evolved directly by the end of the 1950s into the bestselling British computer with a total of nearly 100 machines installed known initially as the HEC4 and later renamed the ICT 1201.