ALGOL
The History of Computing - Een podcast door Charles Edge
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Today we’re going to cover a computer programming language many might not have heard of, ALGOL. ALGOL was written in 1958. It wasn’t like many of the other languages in that it was built by committee. The Association for Computing Machinery and the German Society of Applied Mathematics and Mechanics were floating around ideas for a universal computer programming language. Members from the ACM were a who’s who of people influential in the transition from custom computers that were the size of small homes to mainframes. John Backus of IBM had written a programming language called Speedcoding and then Fortran. Joseph Wegstein had been involved in the development of COBOL. Alan Perlis had been involved in Whirlwind and was with the Carnegie Institute of Technology. Charles Katz had worked with Grace Hopper on UNIVAC and FLOW-MATIC. The Germans were equally as influential. Frederich Bauer had brought us the stack method while at the Technical University of Munich. Hermann Bottenbruch from The Institute for Applied Mathematics had written a paper on constructing languages. Klaus Samelson had worked on a computer called PERM that was similar to the MIT Whirlwind project. He’d come into computing while studying Eigenvalues. Heinz Ritishauser had written a number of papers on programming techniques and had codeveloped the language Superplan while at the The Swiss Federal Institute of Technology. This is where the meeting would be hosted. They went from May 27th to June 2nd in 1958 and initially called the language they would develop as IAL, or the International Algebraic Language. But would expand the name to ALGOL, short for Algorithmic Language. They brought us code blocks, the concept that you have a pair of words or symbols that would begin and end a stanza of code, like begin and end. They introduced nested scoped functions. They wrote the whole language right there. You would name a variable by simply saying integer or setting the variable as a := 1. You would substantiate a for and define the steps to perform until - the root of what we would now call a for loop. You could read a variable in from a punch card. It had built-in SIN and COSIN. It was line based and fairly simple functional programming by today’s standards. They defined how to handle special characters, built boolean operators, floating point notation. It even had portable types. And by the end had a compiler that would run on the Z22 computer from Konrad Zuse. While some of Backus’ best work it effectively competed with FORTRAN and never really gained traction at IBM. But it influenced almost everything that happened afterwards. Languages were popping up all over the place and in order to bring in more programmers, they wanted a formalized way to allow languages to flourish, but with a standardized notation system so algorithms could be published and shared and developers could follow along with logic. One outcome of the ALGOL project was the Backus–Naur form, which was the first such standardization. That would be expanded by Danish Peter Naur for ALGOL 60, thus the name. In ALGOL 60 they would meet in Paris, also adding Father John McCarthy, Julien Green, Bernard Vauquois, Adriaan van Wijngaarden, and Michael Woodger. It got refined, yet a bit more complicated. FORTRAN and COBOL use continued to rage on, but academics loved ALGOL. And the original implementation now referred to as the ZMMD implementation, gave way to X1 ALGOL, Case ALGOL, ZAM in Poland, GOGOL, VALGOL, RegneCentralen ALGOL, Whetstone ALGOL for physics, Chinese ALGOL, ALGAMS, NU ALGOL out of Norway, ALGEK out of Russia, Dartmouth ALGOL, DG/L, USS 90 Algol, Elliot ALGOL, the ALGOL Translator, Kidsgrove Algol, JOVIAL, Burroughs ALGOL, Niklaus Firths ALGOL W, which led to Pascal, MALGOL, and the last would be S-algol in 1979. But it got overly complicated and overly formal. Individual developers wanted more flexibility here and there. Some wanted simpler languages. Some needed more complicated languages. ALGOL didn’t disappear as much as it evolved into other languages. Those were coming out fast and with a committee to approve changes to ALGOL, they were much slower to iterate. You see, ALGOL profoundly shaped how we think of programming languages. That formalization was critical to paving the way for generations of developers who brought us future languages. ALGOL would end up being the parent of CPL and through CPL, BCPL, C, C++, and through that Objective-C. From ALGOL also sprang Simula and through Simula, Smalltalk. And Pascal and from there, Modula and Delphi. It was only used for a few years but it spawned so much of what developers use to build software today. In fact, other languages evolved as anti-ALGOL-derivitives, looking at how you did something and deciding to do it totally differently. And so we owe this crew our thanks. They helped to legitimize a new doctrine, a new career, computer programmer. They inspired. They coded. And in so doing, they helped bring us into the world of functional programming and set structures that allowed the the next generation of great thinkers to go even further, directly influencing people like Adele Goldberg and Alan Kay. And it’s okay that the name of this massive contribution is mostly lost to the annals of history. Because ultimately, the impact is not. So think about this - what can we do to help shape the world we live in? Whether it be through raw creation, iteration, standardization, or formalization - we all have a role to play in this world. I look forward to hearing more about yours as it evolves!