Welcome back to web technology core concepts at Learning Journal. In the earlier session, I
said, a website is a collection
of one or more web pages. So, a website could be as simple as a single HTML page, Right? If you
have
a web page, you can create a website and run it on your local machine. However, no one else on
the
planet will be able to access your website until you take it to the Internet, Right?
So let's talk about taking your website to the Internet. I have this simple web page. This
page
is my website. It is not that great, but this is what I have.
How can I take this website to Internet? What do I need? Just think about it. Tell me at
least
one logical thing. Yes, you are right. The first thing that I need is
a computer with an Internet connection. We all have such computers. But unfortunately,
that
is not enough to make my website available over the Internet. I need at least one more thing.
A web server
I am sure you are wondering with some questions.
- What is a web server?
- Why do we need them?
The Web Server
Let us try to understand the need for a web server and then we will try to define a web server.
Suppose I have a single page website on my laptop. I saved it at the following location
C:\myfirstpage.html.
Now I want to make it available to the Internet. So I connected my laptop to the Internet. As
soon as I connect my laptop
to the Internet, my Internet service provider will assign a unique IP address to my computer.
On
the other side, you are sitting somewhere on this planet with another computer. You also
connected
your machine to the Internet. Technically, there is a connection between our computers and both
of
them have two different unique IP addresses, Right? You should be able to start a browser on
your
laptop and type my website's address. And there comes a series of problems. The first problem
is
this.
What is the address of my website?
Well, it could be the IP address of my laptop and the file name. Something like, the one
shown
below.
http://10.2.0.1/myfirstpage.html
Let's assume that the first problem is solved. Now you can type this address into the web
browser.
The browser will look at the IP address. The IP address is like a telephone number. If the
browser
knows the IP address, it can send some data to the computer with that address, Right? So the
browser
sends a request to my computer asking for the
myfirstpage.html file. That request reaches to my computer. And here comes the next
problem.
No one is there to listen to that request. It is same as a guest is knocking at my door,
but
there is no one in the house to listen and respond. So, we need to have a software that keeps
listening
and responding to such requests. That's what the web server is.
So at the fundamental level, we can think of
a web server as a piece of software that listens and responds to the end users over the
Internet.
It may not be the most appropriate definition for a web server, but this is what a web server
means
at a high level.
Clients and Servers
So the website works using a client-server model. In this model, as the name suggests there are two actors.
- Client
- Server
The client sends a request, and the server returns an appropriate response. In case of our
example, the browser is the client.
It sends a request for the myfirstpage.html page. The web server is the server. It listens for
the
request and returns the myfirstpage.html page to the browser.
Great! The example gives you a high-level idea of how a website works, and we also talked
about
the client-server architecture. We will talk a little more about a web server in an upcoming
video.
See you again in the next video.
Thank you for watching Learning Journal. Keep learning and keep growing.