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And we're going to start Section four with the general info of how the Web works, more specifically

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how we exchange data on the Web and we're going to do that with the help of few slides.

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Now, if you're one of the people who's already reached the daily limit, I hear you once we're done

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with these suckers, I promise will mostly actually write code for the remainder of the course.

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I do believe, though, that before we build an actual Web server, it's crucial for us to understand

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how it works under the hood.

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And that way we'll have a clearer understanding of what tasks need to be done.

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If something is if you can always go back to the slides, you already know where they are located.

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And also as we're going to be progressing with the course from time to time, I will swing back to them

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when I will need to emphasize a specific point.

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With that said, let's talk about how we exchange data on the Web.

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I have to say that if you're watching this video, you know how to use a Web browser.

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But under the hood, the way it works, we open up the laptop, we go to our favorite search engine,

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and then we type the URL, basically the Web address.

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And that way we are performing a request.

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And we are performing a request to the server that is responsible serving of those resources.

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For example, when you look for CNN dot com, you're looking for a server that has those resources and

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then that server sends you back the response and the same work with YouTube, the same works with John

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Smith, dot com or whatever.

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So you just pick a resource.

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You say, hey, can I get this data?

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And then server who is responsible for those resources just sends you back the response.

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Now, that is not using HTP protocol and that's why these ones are called HTP messages.

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So the user sends the HTP request message and then the server sends the HTP response message.

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And that's how we exchange data on the Web.

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And for the remainder of the course, we'll be responsible for building such web server, using node

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and more specifically, Xpress.

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Now talk about why we use Express as well as show you a few examples later on in the course.

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But for now, just remember, yes, we'll use node, but in order to make our lives easier, we'll use

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the framework by the name of ExpressJet.

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And lastly, I would just want to mention that even though name server definitely sounds way cooler

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than the computer, at the end of the day, they're just computers whose job is to always make that

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resource available.

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So, yes, those are computers.

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And yes, there are some differences.

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For example, they most likely don't have the graphical interface or Tegui.

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And also they're probably much bigger than your laptop.

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But at the end of the day, they are computers whose job is to always make sure that that resource is

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available, because imagine if you would have a server that only works from eight to five.

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So if you go to your website at six o'clock at night, you cannot access the resource.

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Probably that's not the service that you would pick.

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So next time when someone asks you.

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If it rains, does the cloud still works, you know what to answer, because the end the day when we

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talk about cloud cloud is just a bunch of these servers, a bunch of these computers connected together.