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Evolution of computer programming languages
The first programming languages predate the modern computer. At first, the languages were codes.
During a nine-month period in 1842-1843, Ada Lovelace translated Italian mathematician Luigi Menabrea’s memoir on Charles Babbage’s newest proposed machine, the Analytical Engine. With the article, she appended a set of notes which specified in complete detail a method for calculating Bernoulli numbers with the Engine, recognized by some historians as the world’s first computer program. But some biographers debate the extent of her original contributions versus those of her husband.
The Jacquard loom, invented in 1801, used holes in punched cards to represent sewing loom arm movements in order to generate decorative patterns automatically.
The first computer codes were specialized for the applications. In the first decades of the twentieth century, numerical calculations were based on decimal numbers. Eventually it was realized that logic could be represented with numbers, as well as with words. For example, Alonzo Church was able to express the lambda calculus in a formulaic way. The Turing machine was an abstraction of the operation of a tape-marking machine, for example, in use at the telephone companies. However, unlike the lambda calculus, Turing’s code does not serve well as a basis for higher-level languages — its principal use is in rigorous analyses of algorithmic complexity.
Like many “firsts” in history, the first modern programming language is hard to identify. From the start, the restrictions of the hardware defined the language. Punch cards allowed 80 columns, but some of the columns had to be used for a sorting number on each card. Fortran included some keywords which were the same as English words, such as “IF”, “GOTO” (go to) and “CONTINUE”. The use of a magnetic drum for memory meant that computer programs also had to be interleaved with the rotations of the drum. Thus the programs were more hardware dependent than today.

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