this:

Objects store data, but to reference and access this data we use the this keyword, as we saw on the previous pages.

Who are the main characters in The Hitchhikers Guide to the Galaxy?

We can also call these details using the name of the function and the keys (hitchhikers.key()):

Who are the main characters in The Hitchhikers Guide to the Galaxy?

So why it this so useful?

Maybe we are working on the code and we update the name of the Object but forget to change the code to be executed:

Who are the main characters in The Hitchhikers Guide to the Galaxy?

But, if we use the this keyword, the not-updated code to be executed still runs:

Who are the main characters in The Hitchhikers Guide to the Galaxy?

However, make sure to us this within its object. Otherwise if we try not to, as in the code below, we call the [Object Window].

Try Me

(Open console and then click the arrow to see the results)

this is set when we call (execute) the function, not when we define it.

What does this mean?

That it is not hoisted.

Let's create a variable, set that vairable as a function expression of the original Object and then call the function:

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