Increment and decrement operators in C programming are used to increase or decrease the value of a variable by 1. The increment operator is denoted by ++, and the decrement operator is denoted by --. These operators can be used with integer and floating-point data types.

Here is an example of using the increment and decrement operators:

#include <stdio.h>

int main() {
  int num1 = 5;
  int num2 = 10;

  num1++;
  printf("num1 after increment: %d\n", num1);

  num2--;
  printf("num2 after decrement: %d\n", num2);

  return 0;
}

In this example, we declared two integer variables num1 and num2 and initialized them with the values 5 and 10, respectively. We then used the increment operator to increase the value of num1 by 1 and the decrement operator to decrease the value of num2 by 1. We printed the new values of num1 and num2 to the console using printf().

The output of the program will be:

num1 after increment: 6
num2 after decrement: 9

The increment and decrement operators can also be used in expressions. When used in expressions, the value of the variable is incremented or decremented before the expression is evaluated.

Here is an example of using the increment operator in an expression:

#include <stdio.h>

int main() {
  int num = 5;

  printf("num++ = %d\n", num++);
  printf("num = %d\n", num);

  return 0;
}

In this example, we declared an integer variable num and initialized it with the value 5. We used the increment operator in an expression to print the value of num and then increment it. We then printed the new value of num to the console.

The output of the program will be:

num++ = 5
num = 6

In summary, the increment and decrement operators in C programming are used to increase or decrease the value of a variable by 1. The increment operator is denoted by ++, and the decrement operator is denoted by --. These operators can be used with integer and floating-point data types and can be used in expressions.