Explain few difference between null, undefined or undeclared JavaScript variable?

devquora
devquora

Posted On: Feb 22, 2018

 

Null is a value that can be assigned to a variable or an object.

Undefined means a variable has been declared but no value is assigned to it. This type of variable is declared itself to be undefined.

Undeclared means the variable has declared without any datatype.

Null, Undefined are primitive data types whereas Undeclared is not a primitive data type.

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