John Backus

John Backus led the team at IBM that developed Fortran, the first widely used high-level programming language that transformed how humans interacted with early computers. Born in Philadelphia in 1924, his career spanned over four decades at IBM, where he influenced both the practical application of code and the formal mathematical structures that define modern programming syntax.

Military Service and Early Education

Before his tenure at IBM, Backus navigated a disjointed academic path. He attended The Hill School and later the University of Virginia, where poor attendance led to his expulsion. During World War II, he served in the United States Army, commanding an anti-aircraft battery. Military aptitude tests prompted his transfer to engineering studies at the University of Pittsburgh and a pre-medical program at Haverford College. After dropping out of medical school and undergoing surgery to replace a cranial bone plate, he was discharged in 1946.

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Fortran and IBM Innovation

Backus joined IBM in 1950 after earning bachelor’s and master’s degrees in mathematics from Columbia University. His early work included calculating lunar positions for the Selective Sequence Electronic Calculator. By 1953, he developed Speedcoding, a precursor to his most significant achievement: Fortran. Introduced to facilitate software development on the IBM 704, Fortran bypassed the need for deep knowledge of machine architecture, establishing a high-level standard that allowed scientists to utilize computers as practical tools.

Formal Notation and Algorithmic Standards

Following his work on Fortran, Backus contributed to the development of ALGOL 58 and ALGOL 60. To resolve complexities in defining the syntax of these languages, he created the Backus–Naur form (BNF). This notation provided a consistent, formal method to describe context-free grammars, becoming a standard feature in compiler development. His work in defining these formal procedures was a primary justification for his receipt of the ACM Turing Award in 1977.

Function-Level Research

Later in his career, Backus focused on the function-level programming paradigm. He introduced the language FP, which he detailed in his 1977 Turing Award lecture, criticizing the traditional von Neumann style of programming. His final project, FL, aimed to evolve these concepts further within IBM. Although these languages saw limited implementation compared to Fortran, they influenced ongoing research into functional programming and the design of subsequent languages like J.