# How to program a computer if you are a child/Actors, sets and accessories

Each developer can create their own actors, their sets, their accessories, and more generally all the virtual beings that are used by computer programs. He or she can also give them to others and copy those of others, when authorized.

To create these virtual beings one writes the scenario of their construction. Such a scenario must contain all the details that say what they are.

To give and copy virtual beings, simply copy and paste the construction scenarios.

### Atoms of virtual beings: numbers

The construction technique is always the same because you do everything with numbers. They are like the atoms of virtual beings. That's why it's very important to know how to count well to program well, and if you progress in mathematics and science, it will be of great service to you, as a developer.

Even texts are constructed with numbers, because we code characters with numbers. A text is then only a sequence of numbers.

There are many techniques to code with numbers everything you see on the screen and what you hear. Sometimes you have to be a good scientist to know these techniques because they are quite sophisticated. You will not understand them if you do not study the sciences.

Some techniques are quite simple. For example the colors on your screen are coded with three small integers per point of the screen, called pixel. The first gives the amount of red, between 0, not at all red, and 255, the maximum red light. The second number does the same for green light, and the third for blue light. In this way computers can display all photographs, all films, all drawings, treating them as series of numbers.

For developers is true this formula of Pythagoras, all is number.

Historical note: Pythagoras is one of the first among the mathematicians and philosophers who left their name in history, about 2500 years ago. You will learn at school, if you have not already done so, the theorem of Pythagoras, like the Greek children in Athens, in the days of Plato and Aristotle, also two great scholars. Pythagoras had noticed that a triangle whose sides are 3, 4 and 5 length units has a right angle between the first two sides. He had also noticed that 3*3 + 4*4 = 9 + 16 = 25 = 5*5. And he understood that it was a general truth: if a triangle has sides that make X, Y and Z units length, the angle between the first two sides is right if and only if X*X + Y*Y = Z*Z.