Difference between null and undefined in JavaScript

Below explain the difference between null and undefined in JavaScript

undefined in JavaScript

The undefined means a variable has been declared but has no value.

var nameTest;
console.log(nameTest); //undefined
console.log(typeof nameTest); //undefined

null in JavaScript

null is an assignment value,Variable declared and is an empty value

var nameTest=null;
console.log(nameTest); //null
console.log(typeof nameTest); //object


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