Programming computers has now reached the stage where it almost does not seem like coding at all, he laborious process of writing hundreds or thousands of lines of computer program language – BASIC, FORTRAN, COBOL, C++, etc – to get the machine to do what you want it to.

We’ve come a long way from the days when computers were “programmed” by re-wiring the suckers, which is not surprising when you see how similar things like ENIAC are to normal telephone switchboards of the era.

In effect all these plugs were the physical representation of ones and zeros, the basic building blocks of digital computing (Analog computing, based on the mathematics of cogs and wheels, had been around for decades and was used in things like the Norden bombsight and submarine torpedo targeting)

10110000 01100001

One step up from binary code was “machine code”, of which the following is represented by a hexadecimal sequence:

B0 61

But even that was pretty clunky. There had to be a a better way and in the early 1950’s, Kathleen Booth invented it: Assembler Language, of which a sample is shown here to do the job above: you can even add a commentary to explain what’s going on (amazing how many developers don’t do that with their creations).

MOV AL, 61h       ; Load AL with 97 decimal (61 hex)

It doesn’t look like it but it’s actually a programming language and the “Assembler” converts it into machine code. It was incremental stuff, but in a short space of time Booth pushed it a long way. Here’s a sample.

[She and her future husband returned to England from the USA and] co-wrote General Considerations in the Design of an All Purpose Electronic Digital Computer (Apexc), and went on to make modifications to the original ARC to incorporate the lessons learnt. Kathleen devised the ARC assembly language for the computer and designed the assembler.

In 1950 Kathleen took a PhD in applied mathematics and the same year she and Andrew Booth were married. In 1953 they cowrote Automatic Digital Calculators, which included the general principles involved in the new “Planning and Coding”programming style.

Here she is loading a program into that Apexc computer that she co-designed with her husband Andrew.

I rather liked writing Assembler code as it made you feel you were in direct control of the machine, and given that the language is often tailored to a specific machine that’s true to a certain extent. Much of the programming of the Apollo spacecraft computers was done in Assembler since there were no technical computer programming languages written to control such unique machines, and that remained true even into the era of the Space Shuttle in the 1980’s.

Booth paved the way for people like one of my personal IT favourites, Margaret Hamilton, who worked for NASA on the Apollo programme and basically invented Software Engineering, the next step along the road to building computer systems.

Kathleen Booth died a few weeks ago at the age of 100 in Canada, where she and her husband had moved in the 1960’s. It would seem that she remained productive to the end of her long and fulfilled life.

Kathleen remained active into her retirement, carrying out research into neural networks which led to the development of a program to simulate the ways animals recognise patterns.

Her husband died in 2009 and she is survived by their son and daughter.