The null value is a unique value representing no value or no object. It implies no object,or null string,no valid boolean value,no number and no array object.
In JavaScript, null
is a special value that represents the intentional absence of any object value. It’s a primitive value. When a variable is assigned null
, it means that the variable does not currently point to any object or value.
Here’s what you need to know about null
in JavaScript:
- Type:
null
is a data type in JavaScript, alongside other primitive types likeundefined
,boolean
,number
,string
, andsymbol
. - Usage:
null
is often used to explicitly indicate that a variable or object does not have a value. It’s different fromundefined
, which typically means a variable has been declared but not assigned a value. - Comparison: When using strict equality (
===
),null
is only equal toundefined
. It’s not equal to any other value, including0
or an empty string. - Object Initialization: Sometimes,
null
is explicitly assigned to objects to clear their value or reset them to an initial state.
Here’s an example of using null
:
let myVar = null;
console.log(myVar); // Output: null
let obj = null;
console.log(obj); // Output: null
In an interview setting, you might elaborate by explaining why and when you would use null
, such as for initialization or to represent a deliberate absence of a value in contrast to undefined
, which may indicate a variable has not been assigned a value yet.