Inctroduction to C language


'C' is a general purpose, Structured Programming language. It is suitable for solving scientific and engineering problems as well as for business application. Over the past few years, C has become the most popular computer programming language. C's speed and power have always made it a favorite language for operating systems, compilers, interpreters and word processors. Many powerful applications can be generated in C language economically and correctly using C language. C language encourages users to write additional library functions of their own to enhance the features of C language. One of the unique features of C language is that it is available on any make of computer and also available for a range of computers, including mainframe, mini and microcomputers.

Types of languages

As we human beings communicate with each other’s in different language such as English, French, German or Arabic. Similarly to communicate with the computers we have to use specific language and for this purpose hundreds of languages have been invented in which few of them has gained international reputation. C language is one of them. Languages can be can be broadly categorized into three categories.

Machine Language

The most elementary and first type of computer, which was invented, was machine language. Machine language was machine dependent. A program written in machine language cannot be run on another type of computer without significant alterations. Machine language is sometimes referred to as the binary language; i-e, the language of 0 and 1, where 0 stands for the absence of electric pulse and 1 stands for the presence of electric pulse. Very few computer programs are actually written in machine language.

Assembly language

As computer became more popular, it became quite apparent that machine language programming was simply too slow and tedious for most programmers. Assembly languages are also called as low-level language. Instead of using the string of numbers, programmers began using English-like abbreviations to represent the elementary operation. The language provided an opportunity to the programmers to use English like words that were called MNEMONICS.

For Example




LDAA = Load Accumulator with A

Add B = Add number B to the contents of the accumulator, leaving the result in accumulator.

High level languages

The assembly languages started using English like words, but still it was difficult to learn these languages. High level languages are the computers language in which it is much easier to write a program than the low-level languages. A program written in high-level language is just like giving instruction to person in daily life. It was in 1957 that a high level language called FORTRAN (Formula Translation) was developed by IBM, which was specially developed for Scientists and Engineers. Other high level languages are COBOL (Common Business Oriented Language), which is widely used for business data processing task. BASIC (Beginners All-Purpose Symbolic Instruction Codes), which is developed for the beginners in 1960s. The most powerful and widely used language is C language which is a general purpose programming language. You can use C language for almost any programming task. PASCAL PL/1 are other high level languages, which has gained widespread acceptance.