What do mean by null in JavaScript?

Why do we use null in JavaScript?

In JavaScript, the value null represents the intentional absence of any object value. null expresses a lack of identification, indicating that a variable points to no object. The global undefined property represents the primitive value undefined .

What is null and undefined in JavaScript?

Null: It is the intentional absence of the value. It is one of the primitive values of JavaScript. Undefined: It means the value does not exist in the compiler. It is the global object.

Is null == undefined?

null is an assigned value. It means nothing. undefined means a variable has been declared but not defined yet.

What do you mean by null?

1 : having no legal or binding force : invalid a null contract. 2 : amounting to nothing : nil the null uselessness of the wireless transmitter that lacks a receiving station— Fred Majdalany. 3 : having no value : insignificant …

Is null and void?

Canceled, invalid, as in The lease is now null and void. This phrase is actually redundant, since null means “void,” that is, “ineffective.” It was first recorded in 1669.

Is NULL better than undefined?

null is a special value meaning “no value”. null is a special object because typeof null returns ‘object’. On the other hand, undefined means that the variable has not been declared, or has not been given a value.

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Why is NULL used?

NULL values are used to indicate that you could have a value, but you don’t know what that value should be yet. They are placeholders until you finally collect the data needed to fill the table field with a real value. You should never confuse NULL values for zeros or blank strings.

Is object NULL JavaScript?

In order to be able to query this difference, JavaScript has null and undefined : While null is – just like in other languages an object, undefined cannot be an object because there is no instance (even not a null instance) available. null is an object.

What is the difference between null & undefined?

Many times we often get confused on what the difference between UNDEFINED and NULL is. Simply put, undefined means a variable has been declared but has not yet been assigned a value. … On the other hand, null is an object. It can be assigned to a variable as a representation of no value.

What is null in JavaScript with example?

A null means absence of a value. In the above example, null is assigned to a variable myVar. It means we have defined a variable but have not assigned any value yet, so value is absence. If you try to find DOM element using document.

Why is null undefined?

Null and Undefined are both data types in JavaScript. Undefined is a variable that has been declared but not assigned a value. … So you can assign the value null to any variable which basically means it’s blank. So by not declaring a value to a variable, JavaScript automatically assigns the value to undefined .

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