I’m currently working on a little project concerning Swedens second computer (or as it was called then an electronic number machine since the Swedish word for computer “dator” wasn’t invented until 1967). While reading the second edition manual for how to code on the computer I came across a wonderful description on the process of writing a program.

Here’s a translation of the text in the image:

After this overview of the main parts of Besk, we will look at the stages in the processing of a problem before it can get to the machine. In practice, the boundaries between the different stages are often blurred, especially if the same person performs several of the operations.

First comes the analysis. This involves the definition and mathematical formulation of the problem, the choice of numerical methods, investigations into accuracy, etc.

This is followed by programming. The programmer also decides in broad terms how the memory is to be allocated, how the quantities are to be represented in the machine - for example, whether it should be constant scale factors or floating point. Often minor changes in the output formulae have to be made after this, e.g. change of variables. It is also decided how the input values and results are to be given, how the calculations are to be checked, which standard codes are to be used, etc. Some of the programming work has direct equivalents in the planning of manual calculations.

This is followed by coding. The coder breaks down the calculation into its elementary components and expresses it as a sequence of characters, which can be punched on a punched tape and transferred to the machine.

The act of “programming” here is just one part of what at least I would now call programming (i.e designing and implementing a system). The act of coding (perhaps what many, erroneously, would call programming) is very mechanically described. Interestingly if you remove the last part of punching in holes into paper, the act of coding is the same now as in 1958, breaking down steps into a sequence of characters.