Inequality in value and type in JavaScript

In addition to the != operator, there is also the !== operator, which takes type into account when comparing. Let's look at the differences between them with examples.

Let the operator != compare two numbers 3. This operator compares values to the fact that they are NOT equal. Since our values are just the same, the condition will be false:

javascriptif (3 != 3) {
  console.log('+++');
} else {
  console.log('---'); // it will work
}

Now let one of our values be in quotes. In this case, the operator != will still consider them equal (since the value is the same, and the type is not important for this operator) and again the condition will be false:

javascriptif ('3' != 3) {
  console.log('+++');
} else {
  console.log('---'); // it will work
}

Let's now compare the two numbers 3 using the operator !==. He will also consider them equal:

javascriptif (3 !== 3) {
  console.log('+++');
} else {
  console.log('---'); // it will work
}

But if we now quote one of the threes, then the operator !== will consider them unequal, since, although their values are the same, they have a different type:

javascriptif ('3' !== 3) {
  console.log('+++'); // it will work
} else {
  console.log('---');
}

javascriptlet test1 = '3';
let test2 = '3';
    
if (test1 != test2) {
  console.log('+++');
} else {
  console.log('---');
}

javascriptlet test1 = '3';
let test2 = '3';
    
if (test1 !== test2) {
  console.log('+++');
} else {
  console.log('---');
}

javascriptlet test1 = 3;
let test2 = '3';
    
if (test1 != test2) {
  console.log('+++');
} else {
  console.log('---');
}

javascriptlet test1 = 3;
let test2 = '3';
    
if (test1 !== test2) {
  console.log('+++');
} else {
  console.log('---');
}

javascriptlet test1 = 3;
let test2 = 2;
    
if (test1 !== test2) {
  console.log('+++');
} else {
  console.log('---');
}