Introduction

C Programming Language

Features of C Programming Language

Low level language support:- C provides low level features and it is closely related to lower level language such as "Assembly Language".

Portability:- C is highly portable that means it can be run on any compiler with little or no change.

Powerful:- C provides wide verity of "Data Types" and "Functions". C provides usefulcontrol and loop control statements too.

High level features:- C is very user friendly as compare to other previous language such as BCPL, Pascal... etc. C collected all useful features of previous language thus C become more effective language.

Bit manipulation:- C can be manipulated using bits, so we can perform different operations at bit level. C supports bitwise operators to manage data at bit level.

Modular programming:- Modular programming is a software design technique that increases the extent to which software is composed of separate parts called modules. C program consist of different modules that can integrated together to form a complete program.

Efficient use of pointer:- C supports efficient use of pointer, and pointer has direct access to memory.

More efficient:- Program written in c language are very efficient and fast. Tish is due to its variety of data type and powerful operators.

Uses of C Programming Language

The C programming language is used for developing system applications on different platform such as Windows, UNIX, LINUX...etc. There are some examples of C being used as follows:-

• Interpreters.
• Network drivers.
• Database systems.
• Graphics packages.
• Spreadsheets.
• Operating system development.
• Word processors.
• Compilers and Assemblers.

Your First C Program

Every C program starts with a main() function. Here is the classic Hello World example with explanations:

/* This is a multi-line comment */
// This is a single-line comment (C99+)

#include <stdio.h>   // Standard Input/Output library

int main() {          // Entry point of every C program
    printf("Hello, World!\n");  // Print to console
    return 0;         // 0 = success
}

/* Compile and run:
   gcc hello.c -o hello
   ./hello
*/

C Program Structure

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

// Global variable
int globalCount = 0;

// Function prototype (declaration)
void greet(char *name);

int main() {
    // Local variables
    int age = 25;
    float height = 5.9f;
    char name[] = "Alice";

    // Input
    printf("Enter your age: ");
    scanf("%d", &age);

    // Output with format specifiers
    printf("Name: %s\n", name);
    printf("Age: %d\n", age);
    printf("Height: %.1f\n", height);

    greet(name);

    return 0;
}

// Function definition
void greet(char *name) {
    printf("Hello, %s! Welcome to C programming.\n", name);
}