- [Equality comparisons](#eqality)

<a name=“equality”/>

JavaScript provides three different value-comparison operations:

1. Strictly equality (===)

triple equals (===) will do the same comparison (including the special handling for NaN, -0, and +0) but without type conversion, by simply always returning false if the types different.

Values are not implicitly converted to the some other value. If the values have different types, values are considered differnt.

2. Abstract Equality (==)

double equals (==) will perform a type conversion when comparing two things, and will handle NaN, -0, and +0 specially to conform to IEEE 754 (so NaN != NaN, and -0 == +0);

3. Object.is

Object.is does not do type conversion and no special handling for NaN, -0, and +0 (it has the same behavior as === except on those special numeric values).

``` javascript

var a = 0;

var b = new String('0');

var c = '0';

console.log(a === a); // true

console.log(b === b); // true

console.log(c === c); // true

console.log(a === b); // false

console.log(a === c); // false

console.log(b === c); // false

console.log(null === undefined); // false

console.log(obj === null); // false

console.log(obj === undefined); // false