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There are over 200 problem-oriented languages. Most of the languages are oriented toward the particular application areas of business or science (math). The most common of them are COBOL, FORTRAN, PL/I, RPG, BASIC, and PASCAL. It is very difficult to determine what are the most popular of modern programming languages. Some languages are very popular for particular kinds of applications (e.g., COBOL is still strong in the corporate data center, often on large mainframes, FORTRAN in engineering applications, and C in embedded applications), while some languages are regularly used to write many different kinds of applications.
COBOL was the most widely used business-oriented programming language. Its name is an acronym for Common Business-Oriented Language. 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 sentence-like 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.
BASICis the acronym for beginner's all-purpose symbolic instruction code. It was developed in Dartmouth College as an easy-to-learn programming language for students and inexperienced programmers and used as a teaching language. Its key design goal is simplicity. BASIC has become a very popular language in systems where many users share the use of a computer through terminals and it has become a universal language for personal computers. The language BASIC is mathematically oriented, that is, its typical use is to solve problems of a mathematical nature. Because BASIC programs are usually executed from a terminal or microcomputer where input is entered through a keyboard and printed output is relatively slow, problems of a business nature requiring large volumes of input-output data are usually not practical.
PASCALwas invented in 1970 in Switzerland. It was named after the mathematician Blaise Pascal, who invented one of the earliest practical calculators. PASCAL is a mathematically oriented programming language and, as such, is most commonly used in mathematics, engineering, and computer science departments of colleges and universities. This language is somewhat unusual in that it was designed to be a structured language. This means that the program must be written in logical modules which are in turn called by a main controlling module.
language with features that make it easy to control the computer hardware efficiently. It was used to produce the Microsoft Windows operating system. It is portable, i.e. programs written in C++ can be easily adapted for use on many different types of computer systems.
a complete program. Visual Basic is used to write general purpose applications for the Windows operating system. The language not only allows programmers to create simple graphical user interface (GUI) applications, but can also develop complex applications.
Delphiis similar to Visual Basic. It is also a programming environment for developing programs for the Windows operating system. It has predefined objects that can be chosen from a toolbox. In Delphi, however, the code attached to the objects is written in a form of Pascal. You can think of Delphi as a kind of 'Visual Pascal'. Like Visual Basic, it is often used for general purpose programs.
with a Java extension) is compiled and converted into a format called bytecode (file with .class extension), which can then be executed by a Java interpreter. Compiled Java code can run on most computers because there are Java interpreters, known as Java Virtual Machines, for most operating systems, including MacOS, Windows, or UNIX.
There are open source tools like applet2app which can be used to convert an applet to a stand-alone Java application. This has the advantage of running a Java applet in offline mode without the need for internet browser software.
Java is multi-threaded. A Java program can have multiple threads (parts), i.e. many different things processing independently and continuously.
People are excited about Java because it lets you create moving images and animated drawings. You can also create graphical objects (e.g. bar charts, graphs, diagrams) and new 'controls' (e.g. buttons, check boxes, pushbuttons with special properties). A web page that uses Java can have inline sounds that play in real-time, music that plays in the background, cartoon style animations, real-time video and interactive games.
One alternative technology is ActiveX, the Microsoft product for including multimedia effects on web pages. Another competitor is Macromedia's Shockwave, a plug-in that lets you animate pictures, add sound and even make interactive pages so that people can play games on websites.
1. Decide if the statements are true or false and correct the false ones.
2. Complete the table:
3. Answer these questions about special features of the languages:
· Which language was used to write the Windows operating system?
· What computer language is called a portable one?
· What is HTML used for?
· Which languages can only be used in the Windows operating system?
· Which language cannot be used for writing programs?
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