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A brief history of programming

A programmable computer needs to be, well, programmed. So, of course, the history of programming goes hand in hand with the evolution of computers.

In 1833, Charles Babbage met Ada Lovelace, daughter of poet Lord Byron. She became very impressed and interested in Babbage's plans for his programmable machines, and their collaboration began. Among other things, she wrote some notes outlining her ideas for how the Babbage Analytical Engine could be programmed. We can call her the inventor of programming, even if we had to wait over 100 years until we had the machine that could make her ideas come true. Her status today is summarized in a History Extra article, from 2017, by James Essinger:

Today, Ada is quite rightly seen as an icon of feminist scientific achievement, a heroine of the mind, and one of the earliest visionaries in the early history of the computer.

In her notes, Lovelace did a couple of remarkable things. The first was that she wrote an algorithm for how Bernoulli numbers, a sequence of rational numbers often used in number theory, could be calculated by the Analytical Engine. This algorithm is considered by many to be the first computer program. Second, she outlined the future of what these machines could do, and, in her vision, she saw that they could be used to draw pictures and compose music. The fact is that when we finally could build a computer, the way they were programmed was heavily influenced by her ideas:

Figure 1.3: Ada Lovelace, aged 17 (portrait by Joan Baum; PD-Art)

The first digital computers were programmed using machine code – the only thing a computer understands. Later in this chapter, we will talk more about machine code and explore what it is. And, as you will discover, it is just a sequence of numbers.

In 1949, John Mauchly proposed something called Brief Code, which was later renamed to Short Code. Short Code can be considered to be one of the first higher-level programming languages. A higher-level programming language is a way for us to write instructions to the computer in a way that is more understandable to humans, which is better than a machine code. The Short Code program is then translated into machine code, and it is that code that the computer executes.

In 1954, the language Fortran was invented at IBM, by John Backus, and this can be considered to be the first widely used high-level, general-purpose programming language. Fortran is, in fact, still in use.

The 1950s saw the birth of some other languages that have also survived, such as Lisp and COBOL. Since then, we have had over 2,300 new programming languages. In the next chapter, we will look at how programming languages have evolved and how they are related, but also why people keep inventing new ones.

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