fromTheSprawl, I found your explanation quite helpful. So, what I understand that integer is a primitive type of variable and all primitive types of variables are compared by value even if we use == which compares by reference. And for strings, I should use .equals().
But I am still confused as to what "reference" means in java. What is a reference? And when we say that == compares references instead of actual values, what is it actually comparing if not value?

CasiOo: Can you explain what you mean by "hashcode" of the object? And how is it different from the value of the object?

If I replace == with .equals("no"), it does work and the program ends. But I don't get why it works. Doesn't == mean that if the value of string is "no" (the person types no), it should terminate the program, like I want? Or does == imply something else. Also why does == work fine with integer but gives me a problem when I attempt to use string? Actually I just want to understand my mistake, so you'll have to excuse me if I am asking a very obvious question.

Here's the whole code

import java.util.Scanner;
public class Addloops {
public static void main (String[]args) {
Scanner scan=new Scanner(System.in); boolean b=true;
while (B)/> {System.out.println ("How many numbers do you want to add to one another?");
int x=scan.nextInt();
int y=0; System.out.println ("Enter " + x + " numbers");
for (int i=0;i<x;i++) {
int z=scan.nextInt();
y=y+z;}
System.out.println ("Your answer is " + y);
System.out.println ("Thank you for using the software");
System.out.println ("Do you want to use the software again? yes or no?");
Scanner s=new Scanner(System.in);
String a=s.nextLine();
if (a=="no") {System.exit(0);}}
}}