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And you might get a question like this, what will do logged in the first example and in the second

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example.

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To answer correctly, you must understand the difference between null and undefined inside JavaScript,

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as you can see here, we have two examples.

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In first example, we didn't assign anything to our variable, which means this variable is not defined

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yet.

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This is why we went here with console.log this variable.

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It will be equal undefined and here after this were console.log and the type of this variable and the

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name of the type will also be undefined.

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And here we have our second example where inside our variable tool were signed null value and here were

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console.log Envato.

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And as you can understand, here we have our value now.

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This is what we will see on the screen.

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But type of variable too will be an object because there is no such type as now.

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This is why the type of variable is an object.

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Let's check this out and alert the page and we get in here and define it.

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This is our variable one here saw the value of it is undefined.

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The type of undefined is undefined as screen.

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Now, after this work, console.log invert to here where I get now.

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This is our value and type of variable to is an object.

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So you really must distinguish in JavaScript between now and undefined undefined.

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It means that the variable is declared, but the value is not assigned yet inside this variable.

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This is exactly what we have here on Line three and null in JavaScript is an assignment value, which

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means it's a value that we can assign inside the variable in our case here, where sign in null inside

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variable tomb.

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And even if you answered correctly here into the human might ask you.

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But what is really the difference between now and undefined?

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Well, we need to use null and when we need to use and define it.

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And actually, it is a tricky one because normally in normal languages, we have only a single property,

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which means that the variable does not exist, for example, Neal.

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But in JavaScript, we have two different things.

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We have undefined and we have now.

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And actually, it really depends on your coattail and your team because you can use both of them inside

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project.

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But for example, I prefer to always use on Nahles and try to have as little undefined INTs as possible.

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But obviously, if you are trying to find a value inside the ray, you will get that undefined and not

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null because we didn't find anything.

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So the answer here that it is fine to use both of them and that is not really something better in one

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or another.