John Backus

John Backus
John Backus
Born	John Warner Backus; 3 December 1924 (age 101); Philadelphia, Pennsylvania, U.S.
Died	17 March 2007 (aged 82); Ashland, Oregon, U.S.
Occupation	Computer scientist
Years active	1950–1991
Known for	Development of FORTRAN, creation of Backus–Naur form (BNF)

John Warner Backus (December 3, 1924 – March 17, 2007) was a pioneering American computer scientist who headed the development team behind FORTRAN, recognized as the first extensively used high-level programming language. He is also credited with creating the Backus–Naur form (BNF), a widely accepted notation for describing syntax in formal languages. In his later career, Backus explored the function-level programming model and delivered the notable 1977 Turing Award lecture titled "Can Programming Be Liberated from the von Neumann Style?"

In 1967, the IEEE honored Backus with the W. W. McDowell Award for his work on FORTRAN. He was awarded the National Medal of Science in 1975 and subsequently received the 1977 Turing Award "for profound, influential, and lasting contributions to practical high-level programming systems, notably FORTRAN, and for formal procedures specifying programming languages."

Backus retired from professional work in 1991 and died at his residence in Ashland, Oregon on March 17, 2007.

Early life

Born in Philadelphia and raised in nearby Wilmington, Delaware, Backus attended The Hill School located in Pottstown, Pennsylvania. His academic performance there was unremarkable. He initially enrolled at the University of Virginia to pursue chemistry, but was dismissed within a year due to inadequate attendance. During World War II, he was drafted into the United States Army, where he attained the rank of corporal and commanded an anti-aircraft unit stationed at Fort Stewart, in Georgia.

Following a strong performance on a military aptitude examination, the Army assigned him to study engineering at the University of Pittsburgh. He later shifted to a pre-medical curriculum at Haverford College. While completing a hospital internship, he was diagnosed with a cranial bone tumor, which was surgically removed and replaced with a metal plate. After briefly attending medical school at the Flower and Fifth Avenue Medical School, he withdrew after nine months. Demonstrating resourcefulness, Backus designed and installed his own replacement plate before receiving an honorable medical discharge from military service in 1946.

Fortran

Upon moving to New York City, Backus trained as a radio technician and developed a keen interest in mathematics. He earned both a bachelor's degree in 1949 and a master's degree in 1950 from Columbia University, specializing in mathematics. In 1950, he joined IBM, initially working on the Selective Sequence Electronic Calculator (SSEC), where he programmed calculations for determining the Moon's trajectory. In 1953, he developed Speedcoding, which became IBM's first high-level programming language designed to facilitate software creation on the IBM 701.

Aware of programming's inherent difficulties, Backus led a project starting in 1954 to create Fortran for use with the IBM 704. As the inaugural widely embraced high-level programming language, Fortran enabled scientists and professionals lacking extensive hardware expertise to program effectively, greatly broadening IBM’s customer base.

Backus–Naur form

John Backus played a significant role in international committees responsible for the creation of ALGOL 58 and the highly influential ALGOL 60, which became the worldwide benchmark for documenting algorithms. He pioneered the Backus–Naur form (BNF), a formal syntax used to define any context-free programming language, as outlined in the UNESCO report on ALGOL 58. BNF was instrumental in advancing compiler construction and had become a standard technique by the 1970s, utilized by tools such as yacc. This contribution led to Backus receiving the distinguished Turing Award in 1977.

Function-level programming

In his subsequent work, Backus concentrated on function-level programming through his language FP, which he introduced during his Turing Award lecture titled "Can Programming be Liberated from the von Neumann Style?". Although FP saw limited practical use outside academic environments, it stimulated extensive research into functional programming. Frequently confused with conventional functional programming paradigms, FP was inspired by Kenneth E. Iverson's APL and utilized a distinct character set. An interpreter for FP was distributed as part of the 4.2BSD Unix operating system.

Later in his career, Backus developed FL, an IBM internal project intended as FP's successor. Development of FL concluded upon project completion; however, documentation remains minimal and its compiler source code was never made public. Unlike many 1980s functional languages grounded in lambda calculus and static typing, FL emphasized combining primitive operations in a manner similar to APL. Numerous ideas from FL influenced subsequent languages, including Iverson's later creation, the J programming language.

Awards and honors

Designated an IBM Fellow (1963)
Recipient of the W. W. McDowell Award (1967)
Awarded the National Medal of Science (1975)
Honored with the Turing Award (1977)
Elected Fellow of the American Academy of Arts and Sciences (1985)
Conferred Doctor honoris causa by Université Henri-Poincaré (1989)
Awarded the prestigious Draper Prize (1993)
Inducted as a Computer History Museum Fellow for pioneering FORTRAN and contributions to computer systems theory (1997)
The asteroid 6830 Johnbackus named in his memory (2007)

External links