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And lastly, I would just want to reiterate the point that even though you might not write your own

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event, events are a core building block of note.

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And effectively, as you're building and writing out the code for your node and application, you are

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using those events at the end of the day anyway, because a lot of built in modules rely on them.

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As a quick side note, if you'd like to see the code that we wrote in previous to lectures, you can

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just navigate to 13 event a matter and not assure that our quickly set up a server.

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And again, the code for this one you can find at 14 and then request event.

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So copy all the contents from the file and just copy and paste and notice something interesting.

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Again, yes, we're getting the module and remember the setup that we have used so far where we go with

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HTP create server and then we pass in this callback function and then of course the callback function

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will be invoked every time someone visits our server.

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So every time the request comes in.

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Now there's another way how we can set it up by using event API.

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So we still create a server, we go with HTP and then create server function.

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But instead of passing in the callback function like we did previously, server has the method on does

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that ring a bell?

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Remember our previous example?

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We had our own instance and it had the method of on.

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Correct.

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So the same goes for server.

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So server has the method on and we listen for request event.

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And when that request comes in, then of course again we have the callback function that handles it.

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So behind the scenes server omits the request event and then of course we can listen for it.

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We can subscribe to it.

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Listen for it or respond to it however you want to call it.

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And the way we do that, we go with server on.

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And then this is a specific name because, of course, it omits that specific name behind the scenes.

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So make sure that it is a request and then the same spiel.

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Now, how do I know that?

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Well, if we go to no documentation and if we look for HTP, we keep on scrolling, keep on scrolling,

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eventually we'll hit the server and or here I can see that it is a class.

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OK, that's a good start.

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And what do you see here?

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Well, I see the event right.

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And what is the event while the name is a request.

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So that's how I know that on my server, the instance that I create has the ability to listen for request

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events.

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And if you want to dig deeper, you can just click on a server.

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You notice that it extends the net server and if we keep on digging, check it out.

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So this one extends what?

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It extends the event amateur.

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So hopefully that makes it clear that even though you might not be setting up events on your own, a

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bunch of built in modules rely heavily on this concept of events.