In programming, a return value is the value that a function sends back to the calling code after performing its task. The return type of a function specifies the data type of the value it will return. Here are common return types and their meanings:

• void:
  Indicates that the function does not return any value.
  Example:
  void printMessage();
• Integer Types (int, short, long, etc.):
  Used for functions that return whole numbers.
  Example:
  int addNumbers(int a, int b);
• Floating-Point Types (float, double):
  Used for functions that return decimal or floating-point numbers.
  Example:
  double calculateAverage(double arr[], int size);
• Character Type (char):
  Used for functions that return a single character.
  Example:
  char getFirstCharacter(char* str);
• Pointer Types:
  Functions can return pointers to various types, indicating memory addresses.
  Example:
  int* allocateMemory(int size);
• User-Defined Types:
  Functions can return values of custom-defined structures or classes.
  Example:
  struct Point calculateMidpoint(struct Point p1, struct Point p2);
Program.c
#include <stdio.h> // Function returning int int addNumbers(int a, int b) { return a + b; } // Function returning double double calculateAverage(double arr[], int size) { double sum = 0.0; for (int i = 0; i < size; ++i) { sum += arr[i]; } return sum / size; } // Function returning char char getFirstCharacter(char* str) { return str[0]; } int main() { // Using the functions int sum = addNumbers(5, 7); printf("Sum: %d\n", sum); double numbers[] = {2.5, 4.0, 6.8, 9.1}; double average = calculateAverage(numbers, 4); printf("Average: %lf\n", average); char firstChar = getFirstCharacter("Hello"); printf("First Character: %c\n", firstChar); return 0; }

Output:
Sum: 12
Average: 5.350000
First Character: H