Null & Undefined
Learn two more variable types in JavaScript: null and undefined. Learn what they represent, how they differ, and how to use them.
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There are two more variable types that we should discuss.
undefined
undefined is meant to represent the idea that something doesn’t exist. When we try to use a variable that has no value, we get undefined. Here’s an example.
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let variable;console.log(variable); // -> undefined
When we declare a variable using let but don’t give it a value, it receives the default value of undefined. This is JavaScript telling us that we’re trying to use something that isn’t there.
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