Ternary operator (They have three operands)

condition ? value1 : value2

The value of the above expression is
either value1 if the condition is true
or value2 if it is false.

Example 1:

if (count == 0)
    Avg = 0;
else
    Avg = sum / count;

same as

Avg = (count == 0) ? 0 : sum / count;
      Boolean expression                        value if Boolean is false
                                              if
                                                   value if Boolean is true

Example 2:

import java.util.Scanner;

public class Tester
{
   public static void main(String [] args)
   {
	int x, y ;

	Scanner input = new Scanner(System.in);
	System.out.println("Enter your score");

	x = input.nextInt();

        y = x >= 0? x : -x;

	System.out.println("Absolute value of "+ x + " is " + y + ".");
   }
}