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There are many different languages that can be used to program a computer. The most basic of these is the machine language. This is the natural language of the computer, the language around which the hardware is built. As each machine has a different hardware, the instruction set of this language varies from machine to machine. This language is also very cumbersome to use. It is just a collection of numbers. A program written in this is difficult to understand and will not work, unless completely rewritten for another type of computer.

 

The same machine language with some additional facilities is called assembly language. Assembly language instructions match machine language on a more or less one-to-one basis. It however uses character strings (mnemonics) which are easier to understand and comments may be incorporated, and memory locations may be referred to by names instead of numeric addresses. It is therefore more convenient to use than machine language. As it is therefore more convenient to use than machine language. As it is very close to the inherent architecture, assembly language can be used to do a lot of manipulations. It however still suffers from the same lack of transportability and is still as cumbersome as machine language. Assembly language is used in writing system software routines that need close communication with the hardware for good performance.

 

Computer languages normally used by programrs for applications are known as high level languages. The instruction sets of these are more compatible with human languages and human thought processes.

 

Depending on the instruction sets and the data handling ability, these languages have various arenas of use. Some languages have instruction sets peculiar to particular types of application and are therefore special purpose languages.

 

Earlier every computer hardware manufacturer used to release their own version of these higher level languages. The industry has now accepted standards for almost all major languages - the manufacturers now provide languages that adhere to these standards and sometimes add some special features of their own. One such body that sets standards is American National Standard Institute called ANSI. Committees of scientists have also set standards for some languages.

 

One of the most easy to use languages, normally used by beginners, but nevertheless capable of complex use, is BASIC. An acronym for Beginners All purpose Symbolic Instruction Code, this was developed originally at Dartmouth College by Kemeny and Kurtz in the mid-1960s. It is very popular and available on virtually every machine. Particularly sophisticated versions are available on Microcomputer, where BSIC has been found to be an eminently suitable programming, where BASIC  has been found to be an eminently suitable programming language. It is normally recommended for beginners to learn programming with, though users range from students to aerospace scientists.

 

The scientific community usually prefers another language, FORTRAN, with derives its name from Formula Translation. Meant specifically for number crunching and being mathematical by nature, it is the most common language used while developing software for large computations. It is also one of the languages being modified for use with supercomputers and parallel processors, some of the most powerful computers, to harness the power of these computers best. A compact language, it is notable for its ease in representing mathematical expressions.

 

For the business community, COBOL (Common business oriented language) has usually been the chosen language to develop application software. It is a procedural language, intended as a means for the direct presentation of a business program to a computer. Quasi-English in nature, it has sentences, formed into paragraphs, arranged into divisions. Because of its nature, non-programrs in business find it easier to understand. However it is verbose and not suited to mathematical functions like FORTRAN. Nevertheless, it has ruled the roost for many years in business application, and most business application software in use over the years has been developed in COBOL.

 

Programming as a structured discipline can be seen in the language PASCAL, developed by Wirth and named after the French man Blaise Pascal (who developed mechanical calculator in 1642). Made available by the early 1970s it seeks to address the ever-increasing difficulties in reading and writing software. It has a small vocabulary and is simple and easy to learn and use. It is a popular language for professional programrs over the world and is increasingly being used to teach programming.

 

A relatively new language becoming increasingly popular is C.C. is not a very high level language and has a small vocabulary but its absence of restriction makes it more convenient and effective than other languages for many tasks. Usually going hand in hand with UNIX, the operating system that has a good chance of emerging as an industry standard, C is picking up.

 

There are several other languages-both high and low level which are in use-each with its strong points and special areas of application. Some are fading away, some may become more popular, and some though popular and in use, are not too well known in India.

 

Algol (Algorithmic Language) was developed jointly by an international group of mathematicians, in Europe and America and is a block structured and modular language. More popular in Europe it is well suited for structured programming. It is the language used for system software in computers made by Burroughts, and is similar to Pascal.

 

PL/1 (Programming Language -1) similarly is a language for both scientific and business applications, having features of both FORTRAN and COBOL. Backed by IBM in early 1960s, it was used on their systems. More difficult to learn, it is not too well known now, though a subset of it is available on PCs.

 

The Department of Defense, USA, sponsored Ada (named after Lady Ada Lovelace, often called the first programr) for its military work. A difficult language to learn, it is used mainly for military work in the USA.

 

As artificial intelligence is growing as a field, its special requirements have led to the developed of languages geared for them. The two popular languages used to develop artificial intelligence systems are Lisp and PROLOG. Lisp is widely used in the USA, whereas the Japanese have standardized on PROLOG.

 

A new type of language called Object Oriented Programming language is emerging. C++ and SMALLTALK are two such languages. These languages are inherently geared towards creating more user friendly systems.

 

There is much talk nowadays of fourth generation languages- 4 GLs. However there is as yet no clear definition of what one is, and if one manufacturer claims his product is a 4 GL, the other disclaims it and calls his product a true 4 GL instead! Broadly speaking a 4GL is an environment which greatly facilitates the development of a system, by defining what it should do. It has several utilities for designing screens and reports, supports a good database and uses an English-like procedural or non-procedural language. These results in considerable amount of time saved if an application is developed in a 4 GL instead of a third generation language. Some examples of 4gls are those provided in ORACLE, FOCUS, INGRESS, INFORMIX and Dbase IV.