FORTRAN became the breakthrough proof that scientists and engineers could describe calculations in a high-level language without surrendering the performance of hand-coded machine instructions. Its success came from a team whose members attacked language design, optimization, arithmetic translation, input/output, documentation, and compiler implementation from different angles.
FORTRAN was a software investment made to lower the cost of using IBM hardware. The compiler took years longer than planned, but it made scientific programming dramatically more productive and helped turn software into a strategic corporate asset.
Before leading FORTRAN, John Backus built Speedcoding for the IBM 701, an interpretive system that made floating-point scientific programming easier while exposing the performance cost of abstraction.
FORTRAN did more than introduce convenient mathematical notation. Its compiler proved that a high-level language could produce code efficient enough for serious scientific work.
The compiler did more than translate code. It renegotiated who could program, what programmers had to remember, and how far human intent could move from machine detail.