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to my questions puzzles me. 5. As far as I know, FORTRAN is primarily used for
scientific work . Are there any programming languages that can perform other tasks? 6.
At present, computers are used to control railway signalling, aircrafts, fax amchines, cars
and a lot of other thigs and processes.
to anwser human beings to employ to perform
application to operate nowadays commands
TEXT 5A
PROGRAMMING LANGUAGES
Most courses in the programming begin with a lesson on the binary system, although
most programmers seldom have to use the binary number in actual practice. The reason for
studying the binary system is to understand the nature of the computer and the way it
operates. Understanding the binary system and its correspondence to the switches inside
the machine helps to take the mystery out of computers. Above all, it is the programmer
who must realize that the machine is controlled by human beings - and that he is the one
who is going to control and direct it.
We know that the machine reacts to a series of electrical impulses that can be
represented in binary numbers. This is called machine language, and the central processing
unit has been designed to execute instructions given to it in machine language. We also
know that all data are translated into binary code before being stored in main storage. It
would, however, be very tedious and difficult to write all information in binary code. Most
programmers therefore use one or more of the standard programming languages to prepare
their programmes. These programming languages use a combination of numbers,
characters, and other symbols that is more convenient and easier to work with than
machine language.
There are many programming languages. They are known by such names as
FORTRAN, COBOL, ALGOL, PL/1, and APL. FORTRAN is used primarily for scientific
work, and COBOL is used for most commercial applications. COBOL and FORTRAN
are the most common of the programming languages. Of the others, ALGOL and APL
are used primarily for scientific work, while PL/1 is employed for general-purpose
programming.
How does the machine understand instructions in one of these languages if the only
language to which the machine can react is machine language? It understands them by
means of interpreter, just as an American diplomat at the United Nations communicates
with a Chinese diplomat through an interpreter. The interpreter for a computer is a systems
program. The systems programmes are part of the software, but they are supplied by the
manufacturer of the machine. One of the systems programmes is called the compiler. The
computer takes each instruction in the programme and translates it into machine language
- that is, into a binary equivalent. It is this translated programme that activates the millions
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