History of Structure of C Program

1. Basics of C Programming
History • Structure • Data Types •
Operators • Decisions
S.Prabhadevi,
Assistant Professor,
Department of Computer science,
Sri Sarada Niketan College of Science for
Women, Karur.

2. Slide 2: History of C
● Developed by Dennis Ritchie at Bell Labs (1972)
● Evolved from B and BCPL
● Designed to develop the UNIX operating system
● Influenced many modern languages: C++, Java, C#, Python

3. Slide 3: Importance of C
● Fast, efficient, and powerful
● Portable across systems
● Ideal for system programming and OS development
● Standard language for embedded systems
● Foundation for many higher-level languages

4. Slide 4: Structure of a C Program
● Preprocessor directives (e.g., #include <stdio.h>)
● main() function – starting point
● Variable declarations
● Statements and expressions
● Return statement (return 0;)

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

6. Slide 5: Data Types in C
Primary Data Types
● int – integers
● float – decimal values
● char – characters
● double – large decimal values
● void – no return value
Derived Types
● Arrays
● Pointers
● Structures
● Functions

7. Slide 6: Constants & Variables
Variables
● Named memory locations
● Must be declared before use
Constants
● Fixed values that do not change
● Types: Integer, Float, Character, String constants
● Declared using const keyword

8. Thank You