 History 2
kfz-tech.de/YC23
Programming consists of a set of commands that are entered and then executed step by step by the computer, which used to be called a 'calculator' earlier. The term was also justified by the
German language, because it was really only possible to calculate.
But the computer could already do that from the very beginning. This is perhaps due to the simplicity of a bit-based structure, which, not coincidentally, is truly unique to computers. In Pascal,
this was written as 'Inc(x)' for the variable x, while in C it became 'x++' or '+= x'.
This example also illustrates one reason why Pascal fell out of favor; among other things, it was simply too verbose. C has far fewer keywords. But we were still at the very beginning. The
question remains: why does a computer only understand zeros and ones?
Simple answer: If Konrad Zuse used relays for his computers in the mid-20th century, and they were still able to perform calculations, then it's clear where the zeros and ones come from. A
relay only had two switching states.
And the tubes and subsequently the transistors did the same as the relays, although the latter could very well also produce intermediate tones. The system remained based on binary values (0 and 1), and increasing
such a value by one is one of the simplest operations for a computer.
As the saying goes, not particularly intelligent, but incredibly diligent. One could even add 'fast' to that description. It can solve even the most complex problems, provided they are presented to it in a way that it can
understand.
This leads almost seamlessly to multiplication, where essentially one value is added as many times as the other dictates. The same applies to multiple subtraction during division. The only complicating factor here is the
processing of the remaining rest.
If keyboards had already existed, then zeros and ones would theoretically have been enough. But even then, a kind of 'reset' would have been necessary and perhaps even more keys. Nevertheless, the description of the
task was trnsmitted in bits.
Here is a task in a typical machine language of the time called MIPS, as you can see from the number of bits, there are 32:
000000 00100 00011 00100 000001 00000
We have now added spaces between the elements, but originally it was entered all together, which didn't exactly improve readability, but rather increased the potential for errors. The command actually means: 'Add $4, $3,
and $5', and is padded with zeros to 32 bits. However, written in a more readable assembly language format, it would look like this:
Add $5, $4, $3
This means that the computer should add the value from register 3 to the value from register 4 and then write it to register 5. This is, of course, a very simple program, and one wonders in what form it is presented to a
computer.
| Registers are memory locations with fast access, but with only a small
number available. |
We don't know exactly, but there were punch cards that were read into the computer, and in this form the results were received, usually after a few days. Of course, not with such a primitive program.
32-bit computers—the PC hadn't been invented yet—were only affordable for large computing centers, and there were long waiting times to use them. Lucky are those who have had the opportunity to use these computers,
which are usually limited to university employees.
| 
