Imagine life before smart phones, maybe you remember? What about before computers? Our computer technology looks a lot different today than it did in the past. It’s smaller, lighter, more powerful and a whole lot faster. But who invented the first computer and what did we do before them?
Before the first computer, we used people to do the work that computers manage today. Things like counting money in our banks, keeping track of census data and even the calculations for our rockets at places like NASA! To help make their jobs easier, people who worked with numbers used different tools like an abacus, a slide rule, or even a mechanical calculator.
Despite these aids, calculations often took a long time and people made mistakes. The English mathematician, Charles Babbage, imagined a better way of doing things. He hoped to relieve people of the ‘routine mental labour’ of repetitive mathematics, and eliminate human error. To this end he imagined two different machines, one of which he started to build.
This is a segment of Charles Babbage’s Difference Engine No 1, which was a mechanical calculating machine for the purpose of producing mathematical tables. He worked on his difference engine for 11 years but was never able to complete it.
Babbage’s Difference Engine was different from other early calculators in both its design and intention as well as the purpose of its construction. Unlike other computing machines of the time someone with no mathematical knowledge could turn the required handles to generate the correct answers, provided the machine had been set up by a skilled operator. It would then be capable of solving successive values of polynomials, without any further input required.
In addition to his Difference Engine Babbage also developed a second idea, although it was not realised as anything more than plans and a few test pieces. It was a machine capable of finding the values for any algebraic function. This Analytical Engine, as he called it, anticipated the principles and structures of the modern computer. It was to be a general purpose, programmable machine, in which the storage of information was a separate function to the processing of information. Unfortunately it was never built and we had to wait another 100 years for his ideas to be resurrected.
You may recognise this device as an Enigma machine, a mechanical device used to encode and decode German messages during World War II. While not a computer itself, the solving of its puzzle played an important role in computer design and development.
Much of the effort to break Enigma’s code took place at Bletchley Park, the home of the British Government Code and Cipher School (GC&CS) during World War II. The Bletchley Park codebreakers used special computing devices called Bombes to decipher Enigma-encoded messages. The Bombes, invented by Alan Turing and Gordon Welchman, were electromechanical codebreaking machines that sped up the deciphering of the code each day.
The Enigma machine also influenced further design advances in other cipher machines during the war. Which prompted reciprocal advances in the computing devices used to decode them at Bletchley Park. For example, the Colossus designed to break a later more sophisticated code machine, was partially inspired by the Bombes created to combat Enigma. Colossus is generally recognised as the first semi-programmable computer.
Based in part on his experiences with Enigma and the Bombes, Alan Turing continued his research in the area of computers after the war. He eventually produced the Automatic Computing Machine (ACE) one of the earliest digital electronic computer designs.