What is software engineering? Part 2
Software components must be produced and used in accordance with defined standards, which are called component models. That is what is a component? Component model they can be a lot different answers to the main question: what is a component and how it differs from component?
I should mention (and you probably already own it felt), non-component programming is not the case, and the whole conversation is about what constitutes a component.
What is programming? This process of forcing a more or less large amounts of iron to some useful activity. It's a struggle to do what you want from it. But this struggle with the machine, and this struggle with you, with himself, because there is a tendency to breed endless mess, and when you do something, you fight with yourself. To fight with iron is pointless. Are you struggling with your misunderstanding, inability and so on. And all this struggle is somehow connected with the component, if you think about it.
If you look at the history of computers, for example, I was taught at University to program on two types of computers: analog, which you probably won't see, most likely, never, and now digital. Why don't you see? Because all the analog equipment since the phone is already switched to digital. However, initially, analog computers were a set of readymade components and a big box of wires in front of it in order to connect these components to each other, and to obtain such a function only on the output, or a voltage that simulates the formulation of the problem to be solved for this analog machine. In addition, the digital machine is made of electric elements that are somehow analog. It is a kind of dialectic.
On the left you see a relatively late analog computing machine, the components of which are connected by wires in order to get some desired feature.
And here you see the first digital machine (or one of the first). I once had himself photographed in the library of Harvard University, it was called MARK 1. The letter "K" from the word MARK 1 in the upper right corner fell off. Maybe it is now glued back. You can see the settings of this machine.
Why is this important and why NATO undertook it in the first place? Because you see it's began to develop around the end of the war, and to develop it was not just so, but because it was necessary to make a bomb, and the bomb had to model and calculate, because if every time we did the testing of the bomb, when there was some question, and would not use computer equipment for this, then it is likely the Earth would split in half long ago. It is no coincidence that the Los Alamos national laboratory, which was building a bomb in America, is considered one of the major laboratories, which dictated all sorts of supercomputer, for example, evaluation. Know 24 Livermore test (Lawrence Livermore national laboratory) is still considered classic tests assessing the performance of the computers.
How can this happen? As a rule, the usual program to which you are accustomed, first written, created (developed, tweaked), and then executed. Therefore, to distinguish between always two stages two stages: statics before executing the program and dynamic, when it occurs, what opportunities she gets and what she does in the dynamics.
As hardware and software in the entire history there is a gradual transition from static to dynamic. The dynamics requires new funding instruments, new quality, because it leads to nothing. And, accordingly, when programming, it is possible to distinguish components that are used during the development phase, static, dynamic, or both there and there. And these differences are determined by the architecture of the computing system and basic software, which this car is. You got used to the fact that your car is already equipped with everything necessary: there is an operating system is basic software, or, as they say, platform.
Economists say that there are two kinds of products in industrial production. They are called "Production group and the Production group B". What applies to the group As well? The means of production, and group B mainly commodities.
Goods that are manufactured, are called the means of production or capital goods. And that is directly consumed clothing or food, is a means to commodities. It so happens that the same product refers to the means of production and articles of consumption. Some sugar when you put it in your tea is a commodity, and when you use it for the production of jams is a means of production.