# Models

From the point of view of informatics, to solve any production or scientific problem you need **models**, and the solution itself is described by the following technological chain: "real object - model - algorithm - program - results - real object". In this chain, the link "model" plays a very important role, as a necessary, obligatory step in solving this problem. Under the model, this means a certain mental image of a real object (system), reflecting the essential properties of the object and replacing it in the process of solving the problem.

The model is a very broad concept, which includes many ways of representing the reality under study. Distinguish between material (real) and ideal (abstract) models. Material models are based on something objective, existing independently of human consciousness (any bodies or processes). Material models are divided into physical (for example, auto- and airplane models) and analog, based on processes similar in some respects studied (for example, processes in electrical circuits are analogous to many mechanical, chemical, biological and even social processes and can be used for their modeling). The boundary between physical and analog models can be carried out quite approximately and such a classification of models is conditional.

Even more complex picture is represented by ideal models, inseparably connected with human thinking, imagination, perception. Among the ideal models can be identified intuitive models, which include, for example, works of art - painting, sculpture, literature, theater, etc., but there is no single approach to classifying the remaining types of ideal models. Sometimes these models are all referred to as information. At the heart of this approach is an extensive interpretation of the notion of "information": "information is almost everything in the world, and maybe even everything at all." This approach is not entirely justified, since it transfers the information nature of cognition to the essence of the models used in the process - while any model is informational. This approach to the classification of ideal models seems to be more productive, in which the following are distinguished.

Verbal (text) models. These models use sentence sequences in formalized dialects of natural language to describe a particular area of reality (examples of such models are the police protocol, traffic rules).

Mathematical models are a very wide class of symbolic models (based on formal languages over finite alphabets) that widely use certain mathematical methods. For example, we can consider the mathematical model of a star. This model will be a complex system of equations describing the physical processes occurring in the bowels of the star. A mathematical model of another kind is, for example, mathematical relationships that make it possible to calculate the optimal (the best from the economic point of view) plan for the operation of an enterprise.

Information models are a class of symbolic models that describe information processes (the origin, transfer, transformation and use of information) in systems of a very diverse nature.

The boundary between verbal, mathematical and information models can be carried out very conditionally; perhaps information models should be considered a subclass of mathematical models. However, in the context of computer science as an independent science, separate from mathematics, physics, linguistics and other sciences, it is advisable to single out the class of information models. Informatics has the most direct relation to mathematical models, because they are the basis of computer application in solving problems of different nature: the mathematical model of the process or phenomenon being studied at a certain stage of research is transformed into a computer (computational) model, which then turns into an algorithm and a computer program.