Client server architecture.
Now, besides the many features that they have, the computers on a network, let's say Internet or
Internet, can accomplish two basic actions.
OK.
Requesting and responding.
So these two actions can define the role of a single computer on the network.
The computers, which request their named clients, the ones which respond, are named servers, so
typically computers on a network can have both roles as well.
So basically a Web application works on a client server architecture.
OK, so now first let's grapple with how the architecture works.
The client requests some resources on the server to use and the server produces an appropriate output
to respond to this request.
The basic communication between the client, the server works like that.
Now, today with HTP two, there are some changes in this type of communication.
But again, this isn't necessarily the topic of this course.
So anyway, now let's have a look at how clients and servers are shaped in a basic network.
So a client is a computer that makes requests to a server, right?
In fact, we don't necessarily have to limit a client to a computer only.
Because clients can come up in different shapes and sizes such as your smartphone, laptop, PC and
so on.
Now, also, a piece of software on your computer can be a client, which is requesting yeah, so generally
in a penetration test, the client will mean your Web browser and Web browsers are the first point to
reach a Web application.
And we're going to dig a little deeper into Web browsers and some of the coming sections.
Now, on the other hand, a server is a computer that responds to the request of the client, so servers
likewise come up in many shapes and sizes.
A server is both a piece of hardware, the computer itself, as well as a piece of software.
So that means that there are several different types of servers do what and how they serve, some of
them are Web servers, some of them are database servers.
There's file servers and mail service.
Now, in the real world, a server has a faster CPU, higher capacity of RAM and storage and so on,
many more features than you know, it makes that more resilient than a client.
Although a simple computer can also be a server.
Now, the client server relationship begins when you request a Web page through your favorite Web browser.
So at this point, your computer or your Web browser is a client and the computer is sending you the
response is the server.
So when you type NBA dotcom into the address bar and hit enter, the communication between the browser
and the NBA server will start.
Now, from this pain below, you can observe the requests.
And to be able to display the page properly, the browser requests many resources from the server,
such as the email documents, stylesheet scripts and many more.
You can also display details about the request and responses from this pain.
But again, this is a topic for another video, or you can just look around.
So now let's open another layer so that we can understand the basics of Web applications.