Kathleen Booth is credited with writing the first assembly language

The first assembly language, the human-readable notation that lets a programmer write instructions as short mnemonic symbols instead of raw binary machine code, is credited to the British computer scientist Kathleen Booth (1922-2022). She developed it for the early computers she and Andrew Booth built at Birkbeck College, University of London, in the late 1940s and early 1950s, work documented in the University of St Andrews’ MacTutor History of Mathematics archive. Assembly language was a foundational step in making computers programmable by people rather than only by their builders, and it underlies the entire software stack on which later AI systems were written.