HISTORY OFVPROGRAMMING LANGUAGE

This history was written in the spring of 2000 when I was in eighth grade. For several years after I wrote it, the text was available online and it became a reference for other articles, Wikipedia entries, and even college courses. I have placed the report here for posterity and amusement (how could I have possibly left out Python??). In 2004, I made two updates in response to e-mailed criticisms, but the text is otherwise unchanged. For a more up-to-date reference, I shamelessly point you to Wikipedia. —Andrew Ferguson   A History of Computer Programming Languages Ever since the invention of Charles Babbage’s difference engine in 1822, computers have required a means of instructing them to perform a specific task. This means is known as a programming language. Computer languages were first composed of a series of steps to wire a particular program; these morphed into a series of steps keyed into the computer and then executed; later these languages acquired advanced features such as logical branching and object orientation. The computer languages of the last fifty years have come in two stages, the first major languages and the second major languages, which are in use today. In the beginning, Charles Babbage’s difference engine could only be made to execute tasks by changing the gears which executed the calculations. Thus, the earliest form of a computer language was physical motion. Eventually, physical motion was replaced by electrical signals when the US Government built the ENIAC in 1942. It followed many of the same principles of Babbage’s engine and hence, could only be “programmed” by presetting switches and rewiring the entire system for each new “program” or calculation. This process proved to be very tedious. In 1945, John Von Neumann was working at the Institute for Advanced Study. He developed two important concepts that directly affected the path of computer programming languages. The first was known as “shared-program technique” (www.softlord.com). This technique stated that the actual computer hardware should be simple and not need to be hand-wired for each program. Instead, complex instructions should be used to control the simple hardware, allowing it to be reprogrammed much faster. The second concept was also extremely important to the development of programming languages. Von Neumann called it “conditional control transfer” (www.softlord.com). This idea gave rise to the notion of subroutines, or small blocks of code that could be jumped to in any order, instead of a single set of chronologically ordered steps for the computer to take. The second part of the idea stated that computer code should be able to branch based on logical statements such as IF (expression) THEN, and looped such as with a FOR statement. “Conditional control transfer” gave rise to the idea of “libraries,” which are blocks of code that can be reused over and over. (Updated Aug 1 2004: Around this time, Konrad Zuse, a German, was inventing his own computing systems independently and developed many of the same concepts, both in his machines and in the Plankalkul programming language. Alas, his work did not become widely known until much later. For more information, see this website: http://www.epemag.com/zuse/, or the entries on Wikipedia: Konrad Zuse and Plankalkul.) In 1949, a few years after Von Neumann’s work, the language Short Code appeared (www.byte.com). It was the first computer language for electronic devices and it required the programmer to change its statements into 0’s and 1’s by hand. Still, it was the first step towards the complex languages of today. In 1951, Grace Hopper wrote the first compiler, A-0 (www.byte.com). A compiler is a program that turns the language’s statements into 0’s and 1’s for the computer to understand. This lead to faster programming, as the programmer no longer had to do the work by hand. In 1957, the first of the major languages appeared in the form of FORTRAN. Its name stands for FORmula TRANslat

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