Прочтите текст и объясните, что представляют собой языки программирования. Text 2. PROGRAMMING LANGUAGES

Let's assume that we have studied the problem, designed a logical plan (our flowchart or pseudocode), and are now ready to write the program instructions. The process of writing program instructions is called coding. The instructions will be written on a form called a coding form.^The instructions we write will be recorded in a machine-readable form using a keypunch, key-to-tape, or key-to-disk, or entered directly into computer memory through a terminal keyboard.

The computer cannot understand instructions written in just
any old way. The instructions must be written according to a set of rules. These rules are the foundation of a programming Ianguage. A programming language must convey the logical steps of the program plan in such a way that the control unit of the CPU can interpret and follow the instructions. Programming languages have improved throughout the years, just as computer hardware has improved. They have progressed from machine oriented languages that use strings of binary Is and 0s to prob­lem-oriented languages that use common mathematical and/or English terms.

There are over 200 problem-oriented languages. The most common of them are COBOL, FORTRAN, PL/I, RPG, BA­SIC, PASCAL.

COBOL

COBOL was the most widely used business-oriented pro­gramming language. Its name is an acronym for Common Јlisi-ncss-Oriented Zanguage. COBOL was designed to solve prob­lems that are oriented toward data handling and input-output operations. Of course, COBOL can perform arithmetic opera­tions as well, but its greatest flexibility is in data handling. CO­BOL also was designed as a self-documenting language. Self-documenting languages are those that do not require a great deal of explanation in order to be understood by someone reading the program instructions. The self-documenting aspect of CO­BOL is made possible by its sentencelike structure and the very generous maximum symbolic field-name length of 30 charac­ters. With a field-name length of up to 30 characters, the name can clearly identify the field and its purpose.

FORTRAN IV

The FORTRAN IV language is oriented toward solving prob­lems of a mathematical nature. The name FORTRAN comes from the combination of the words formula translation. The version of FORTRAN IV has been designed as algebra-based programming language. Any formula or those mathematical relationships that can be expressed algebraically can easily be expressed as a FORTRAN instruction. FORTRAN is the most commonly used language for scientific applications.

PL/I
PL/I stands for programming language I. It was designed as a general-purpose language incorporating features similar to COBOL for data handling instructions and features similar to FORTRAN for mathematical instructions. PL/I is much more than a combination of the good features of both COBOL and FORTRAN, as it has many capabilities that are unique. Yet, although PL/I is one of the most versatile and the most power­ful of the programming languages, it is not the most commonlyused. COBOL and FORTRAN have been available for a longer period of time than PL/I, and many more users work with those languages.

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1. What is the process of writing instructions called? 2. What is a code? 3. How must instructions be written? 4. What is the foundation of any programming language? 5. How was the de­velopment of programming languages progressing throughout the years? 6. What are the most common problem-oriented lan­guages? 7. What is COBOL? 8. What functions was COBOL designed for? 9. What does FORTRAN serve for? 10. What ca­pabilities has PL/I?

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