C Language


Name: C Language

Designed By : Dennis Ritchie

First Released On 1972

Developed at : Bell Laboratories
Introduction:

         The C- language is one of the powerful and most popular programming for variety of applications. C has flexible features to write programs for numerical and graphical application of many operating system programs for the latest computer and compiler are written using C- language.

History of C:
  1. The C programming language is a structure oriented programming language, developed at Bell Laboratories in 1972 by Dennis Ritchie.

  2. C programming language derived from an earlier language called “B”(Basic Combined Programming Language- BCPL)

  3. C language was invented for implement UNIX operating system.

  4. In 1978, Dennis Ritchie and Brian Kernighan published the first edition “The C Programming Language” and commonly known as K&R C.

  5. In 1983, the American National Standard Institute (ANSI) established a committee to provide a modern, comprehensive definition of C. The result definition, the ANSI standard, or “ANSI C” was completed late 1988.


Features of C language:
  1. C combines the feature of both assembly level language (low level language) and higher level language. For this reason C is refer to as a middle level language. Hence, it is suitable for developing application software as well as system software.

  2. C supports structured programming and most of the high level mechanism is provided using the concept of function.

  3. Compiler for C is compact and can be easily ported on small machine including PC.

  4. C is rich in data types and operator. C provide rich set of data type of both built in as well as user define data type and it also provide rich set of operators, many of which are not available in other high level languages.

  5. C is extensible. C compiler comes with standard library, which includes the low level code for the standard function. We can also define our own functions and add them to the library and make it available to other programmers. The library can thus be extended by including our own function.

  6. C is portable meaning that C program written for one computer can be run on the other computers also with little or no modification to the program. The popularity of c language is to some extend attributed to it portability feature.

  7. Program written in C are found to execute faster than compared to other languages.

  8. It is easily expendable for the requirement.


Rules for writing a C program:

       Some rules which hold for all programs written in C language are as follow:
  1. Every C program must begin with function called main ().

  2. All statements of C are written in main ().

  3. C is a case sensitive language. Be careful about the upper case and lower case.

  4. Every C statement must end with semicolon (;), thus semicolon act as a statement terminator.

  5. The opening brace ({) and closing brace (}) indicate the body of the program which include instruction to perform the required task.

  6. Use /*----------*/ for multiline comment and // for single line comment.

  7. Keywords cannot be used for any other purpose that is they cannot be used as a variable or function name.

Syntax:
#include <stdio.h>
main()
{
     printf("Hello World");
     return 0;
}

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