Fortran: Who Invented Fortran and Why Was It Created?

Fortran was the first high-level programming language to achieve widespread use, and it is still in active use today. The answer to who invented Fortran and why was it created is straightforward: John Backus led a small team at IBM that designed the language and its compiler between 1954 and 1957, because programming the IBM 704 by hand had become slower and more expensive than the machine time itself. The first compiler shipped in April 1957, and the name came from "Formula Translation".

Who invented Fortran and why was it created

In late 1953 John Backus proposed to his IBM managers that the company develop a more efficient way to program the upcoming IBM 704. He had already written Speedcoding, an interpreter for the IBM 701 that made programming easier but ran slowly. Backus argued that a large share of the cost of running a computer was the cost of programming and debugging it, and that an automatic translator could reduce that cost if, and only if, its output ran almost as fast as hand-written code.

That last condition shaped everything. Programmers of the time doubted that any compiler could match careful hand coding, so Backus's team put enormous effort into optimisation. The group included Irving Ziller, Harlan Herrick, Roy Nutt, Lois Haibt, Sheldon Best, Richard Goldberg, David Sayre, Peter Sheridan and Robert Nelson, among others. A preliminary report on the "IBM Mathematical Formula Translating System" appeared in 1954, and the compiler was delivered to IBM 704 customers in 1957.

Design and key features of early FORTRAN

The original FORTRAN offered features that look basic now but were a major advance in 1957:

• Arithmetic expressions written much like algebra, with operator precedence
• Variables with implicit types: names beginning with I to N were integers, others floating point
• The DO loop for counted iteration
• Arrays of up to three dimensions
• IF and GO TO statements for control flow, including the three-way arithmetic IF
• FORMAT statements for formatted input and output

Code was written in fixed columns to suit 80-column punched cards. Columns 1 to 5 held statement labels, column 6 marked continuation lines, and columns 7 to 72 held the statement itself.

Major versions and standards

The spelling changed from FORTRAN to Fortran with the 1990 standard, which is why modern documentation uses mixed case.

A short code example

Modern Fortran looks quite different from the punched-card original. This free-form program computes the mean of an array using built-in array functions:

program mean_value
  implicit none
  real :: x(5) = [2.0, 4.0, 6.0, 8.0, 10.0]

  print '(A, F6.2)', 'Mean: ', sum(x) / size(x)
end program mean_value

The implicit none line switches off the old I-to-N typing rule, and whole-array operations such as sum replace explicit loops.

How Fortran has been used

Fortran became the standard language of scientific and engineering computing within a few years of its release. It has been used for weather forecasting and climate modelling, computational fluid dynamics, structural analysis, nuclear and particle physics, and quantum chemistry. Foundational numerical libraries such as BLAS and LAPACK were written in Fortran, and the LINPACK benchmark, used to rank supercomputers, grew out of Fortran linear algebra code.

Influence and legacy

Fortran proved that a compiler could produce efficient code, which made high-level programming acceptable to a sceptical industry. It directly influenced ALGOL 58, BASIC and PL/I, and its array orientation lives on in MATLAB and newer scientific languages. Backus himself received the Turing Award in 1977, and he also contributed to the notation used to define ALGOL 60's syntax.

Is Fortran still used today?

Yes. Fortran is actively maintained, with modern compilers from GNU (gfortran), Intel and others, and it remains common in high-performance computing, where large, validated codebases and excellent compiler optimisation make it hard to replace.

Looking back at who invented Fortran and why was it created, the original goal still describes its niche: let scientists write formulas naturally and get machine code that runs about as fast as anything written by hand.

Frequently asked questions

What does the name Fortran stand for?

Fortran comes from "Formula Translation", taken from the 1954 report on the IBM Mathematical Formula Translating System. It was written as FORTRAN in capitals until the Fortran 90 standard adopted the mixed-case spelling.

Which computer was the first Fortran compiler written for?

The first Fortran compiler was written for the IBM 704 and delivered to customers in April 1957. Versions for other IBM machines followed quickly, and FORTRAN IV later spread to many manufacturers.

Why is Fortran still used for scientific computing?

Fortran compilers generate very fast numerical code, and the language has strong built-in support for arrays and parallel programming. Many major simulation codes have been developed and validated in Fortran over decades, so rewriting them would be costly and risky.