All language subtitles for 006 How Do Websites Actually Work__en[UdemyIran.Com]

Now that we've spoken about how the internet works, in this episode

I want to talk about how exactly do websites work. What exactly does HTML,

CSS and JavaScript do exactly? Now, in order to access a webpage,

we all know that you need a browser, right? And that can be Chrome,

Safari, Firefox, whatever is your favorite one.

These are all pieces of software that allow you to look up the IP address of

your website and be able to receive data that it can render into this beautiful

websites that we see. Now,

the data that you receive from the server usually consists of three types of

files; HTML, CSS, and JavaScript.

And it's very likely that you would have come across these types of files or

these words before,

because they're so common and there are so integral to how websites work.

But, what exactly do they do

and why are there so many different types of files?

Why can't we just have one file that's, you know, a website? Well,

they actually have very different jobs.

The HTML code file is responsible for the structure of your website.

So if a website was a house,

then the HTML would be the builder who would come in to build the walls or put

in a toilet. Basically they establish the structure of your house.

And when you write HTML code, you also build up the structure of your website.

So you could use HTML to add an image or button or text box,

whatever it is that you need in your website. Now,

the second type of file are CSS files,

and these files are responsible for styling your website.

If you were building a house, then this would be the painters and decorators.

They would be going around

painting the walls or adding stylistic flourishes to your place,

and generally making the place look the way that you want it to.

And that's exactly what CSS code does as well. When you incorporate CSS,

it allows you to specify how you want your website to look.

So you could say that, yes, I have a button that I got from my HTML,

but that button I want it to be red and I want the text to be white

and I want the font of the text to be an Arial. That is all done using CSS code.

Now the final component is the JavaScript code.

And this is the code that allows your website to actually do things or have

behavior. And if you were building a house,

you would have the electrician come in,

who would be able to connect the wires so that your light bulbs actually switch

on or somebody who comes in and does the plumbing so that your toilet can

actually flush. And the JavaScript code does exactly that.

It allows your website to actually do things and have behavior.

So if we take the Google website as an example again,

once we receive these files from Google server,

when our browser loads up the HTML files, we'll get to see the structure

of the website, namely, there's one image which has their logo,

there's two buttons, and there's a text box where we can enter our search. Now,

when we receive the CSS files,

then that will modify the appearance of all of those components.

We don't have any more buttons or any more images,

but the now look the way that Google wanted it to. And finally,

when we incorporate the JavaScript files,

then our website actually starts having behavior. It has functionality

and it's actually able to do something rather than just display some images and

texts to us. Now, with the knowledge that we've already acquired,

we can already start messing around with websites on the internet.

So open up Chrome and head over to techcrunch.com.

And if you're not familiar with it,

it's basically a technology news website where I get my latest tech news.

Once you're over here,

I want you to right-click on the title here and click on inspect.

Now this brings up the Chrome developer tools,

and we're going to be exploring this in a lot more detail,

but for now we're going to use it to do something really simple.

You can see that when I right-click on that heading and click inspect,

it automatically opens up the entire code file that was used to render this

website. So these are all of the elements that make up this website.

And when you click on inspect,

it will highlight to you the part of the code that corresponds to the thing that

you right clicked, right? In this case, it's this title.

And inside this title, you can see that there is a link,

which means that when you click on it, it'll go to another web page,

but it also got a bit of text. So right inside Chrome developer tools,

if you double click on the bit of text that corresponds to the title,

you can actually edit it.

So let's go ahead and change the front page of TechCrunch.

Let's say something like,

uhm..

So this is a great way of pranking your friends,

especially when they can see that you're on tech crunch.com and the title or any

of the texts on the website is what you want it to say.

And this is a great joke to play on friends who are maybe not quite as

technologically advanced as you,

because they haven't taken the course that you have. Now unfortunately,

when I hit refresh on this website, all of my good work is gone.

And the reason is because when I'm editing it here inside my browser,

I'm actually changing the local copy of this file that I got back from the

server. But when I click refresh,

then that makes a new request to the servers to load up a fresh copy of the

website. So of course, then it updates to the original content.

But in the coming lessons, we're going to be working with HTML, CSS,

and JavaScript so that you can create and host live on the internet,

your very own websites and through learning how to code and how to build

websites

you are going to be able to make websites that say anything that you want it to,

look the way that you want it to, and have the functionality that you need.

So for all of that and more, I'll see you in the next lesson.