var n = "1";
console.log(n==1); // outputs true
console.log(n===1); // outputs false
The equality operator will attempt to make the data types the same before making the comparison. On the other hand, the identity operator requires both data types to be the same as a prerequisite.
There are quite a few other posts out there similar to this questions. See:
How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators differ? (has a nice comparison chart)
In practice, the identity operator comes in really handy when you want to be certain that a boolean value is true or false since...
1 == true => true true == true => true 1 === true => false true === true => true