JavaScript's 'undefined' And 'null': What's The Difference?

What is "undefined"?

In JavaScript, "undefined" is a primitive value automatically assigned to variables that have been declared but have not been initialized with a value. It also represents the value returned by functions that do not explicitly return anything. Essentially, it denotes the absence of a meaningful value.

Example

let x;
console.log(x); // Output: undefined
function doSomething() {
    // Kuch bhi return nahi kiya gaya
}
console.log(doSomething()); // Output: undefined
```
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# Not defined
- In JavaScript Not Defined is a ReferenceError that occurs when you try to use a vari...