Conversion Specifications in C are used in formatted I/O functions like printf() and scanf() to define the type of data to be read or written.
Common Format Specifiers:

Example:
#include <stdio.h>
int main() {
int age;
float height;
char grade;
printf("Enter your age, height and grade (e.g. 20 5.9 A): ");
scanf("%d %f %c", &age, &height, &grade);
printf("You entered: Age = %d, Height = %.1f, Grade = %c\n", age, height, grade);
return 0;
}