Equality

Performs a value equality comparison and returns the result:

var x = { Name : 'Fred' };
var y = { Name : 'Fred' }; 
var z = x == y;  // z == true

Performs a value inequality comparison and returns the result:

var x = { Name : 'Fred' };
var y = { Name : 'Fred' }; 
var z = x != y;  // z == false

Performs an identity equality comparison and returns the result:

var x = { Name : 'Fred' };
var y = { Name : 'Fred' }; 
var z = x === y; // z == false

Performs an identity equality comparison and returns the result:

var x = { Name : 'Fred' };
var y = { Name : 'Fred' };
var z = x !== y; // z == true

If lhs and rhs are both null, the result is false. If lhs or rhs (but not both) is null, the result is true.