Plankalkulation

Plankalkül, also known as Plan Calculus, is the earliest known high-level programming language. It was designed by German engineer Konrad Zuse between 1940 and 1945 for engineering and scientific calculations on his early computers. The project aimed to provide a formal and expressive way to describe algorithms and data structures, well before later languages existed.

The language introduced concepts intended to support structured programming and rigorous problem solving. It offered typed data, including integers and real numbers, as well as more complex data structures such as arrays and records. Plankalkül supported modular program design through procedures or subroutines with parameters, and it included control constructs for conditional execution and iteration. The design also addressed issues of memory organization and addressing of storage locations, reflecting a systematic approach to programming.

Historically, Plankalkül remained largely unknown outside Zuse’s circle for many years and was not implemented on a working machine during the early years of its development. In the following decades, scholars recognized its significance as a precursor to later high-level languages, with many viewing it as a forerunner to concepts later embodied in languages such as FORTRAN. In the late 20th century, researchers and enthusiasts reproduced demonstrations and interpreted aspects of Plankalkül to illustrate its ideas and potential.

The name Plankalkül is German, translating roughly to Plan Calculus or Plan Kalkulation. The language is noted in historical surveys of programming as an important milestone in the evolution of higher-level programming concepts, highlighting Zuse’s early contribution to the field.