Operator ===

Question

could you give me examples about this operator? :)

Answer 1

== is used only to tell that the variables are of the same value.
=== is used to express that the variables have the same value and are of the same type.
Example:
var a="30";
var b=30;
You can say that a==b , but not a===b...
because type is not same

Answer 2

undefined == null -> true
undefined === null -> false
1 + '2' == 12 -> true
1 + '2' === 12 -> false