The null
value represents the intentional absence of any object value; it is one of JavaScript’s primitive values.
The null value is written with a literal
null
.
Unlike undefined
, null
is not an identifier for a property of the global object. Instead, null
expresses a lack of identification; it indicates that the variable does not point to any object. In APIs, null
is often retrieved in a place where an object can be expected, but no object is relevant.
Take a look at the example below, which highlights the use of null
:
my_var;// Executing the above statement will result in a "ReferenceError: my_var is not defined"// my_var does not exist. It is not defined and has never been initialized:var my_var = null;my_var;// my_var is known to exist now but it has no type or value:// Executing the above statement will not throw an error"