In this tutorial, you will learn:
- What is the Internet?
- What are Clients and Servers?
- What is a Network?
- What is an IP address?
- How do I access the Internet?
Click on the image below to watch a video about how the Internet works or if you prefer to read the guide instead, keep scrolling down.
Think of the Internet as a vast network of wires buried in the ground (and sea) running across the globe. These wires can be cables, or fiber optics, but they can also be wireless signals from satellites or radios - they all carry bits of data and information.
Special computers called servers are connected to this wire(s). Think of these as filing cabinets that store information (files) and pass it on when you ask for them. These servers can communicate with another server that is connected to the wire. All these linked-up computers are what make up the Internet - it is a network of computers.
Now that you know what a server is, let's mention two types of servers:
- Local server: This means that you have a server set up on your current machine, it is physically on site with you.
- Remote server: When a server is remote, it is on another computer. You may have heard of the 'cloud' - this is a type of remote server (usually in Data Centres) that you access via the Internet.
So we already know one type of computer - servers - whose job is to store files. A computer that requests for these files is called a client. When you open up a browser - let's say Chrome - and type in www.facebook.com, Chrome is the client asking Facebook's server for the files (Facebook's webpages). The server receives the request and returns the web pages back to Chrome, so you can now get into your Facebook account.
At its most basic, a network is two or more computers that are linked in order to communicate with each other. Here are two very common types of networks:
- Local Area Network (LAN): This refers to when a network of computers happens to be in the same physical location - like a school or office building.
- Wide Area Network (WAN): A WAN connects networks in larger geographic areas like a city, state or a country. A WAN can connect several LANs together.
The Internet just has one job - to move information (known as data) from one place to another. But how does it know where to send this data to?
Every device connected to the Internet has to have an 'address' so that they can be found by another computer (just like a postal address lets the mailman find you). This is called an Internet Protocol address (IP address) and is represented by a series of numbers. For example, the IP address 172.217.7.238 will lead you to the home page of www.google.com. IP addresses let machines find each other on the huge network of computers.
When a client wants to connect to the Internet, it needs to go through an organization called an Internet Service Provider (ISP). An ISP is a company that lets you access the Internet. Yet another type of device called a router exists to use the Internet. A router's job is to connect you to the ISP which in turn gets you to the Internet. It looks like this:
If you have several computers or devices in your home or school, a single router will connect all of them to the Internet. This is done because the router emits radio waves, and if your computer or device is within the range of those waves, you can connect to the Internet wirelessly. This is called a Wifi connection.
Here's another geeky fact - many people think that the Web and the Internet are the same thing, but they're not! The Internet existed well before the World Wide Web was invented. As we have learnt, the Internet is a huge network of computers, while the Web is a service or application that sits on top of this network. The Web is a way of accessing information through the Internet (another way being email, or instant messaging). If the Internet is a library, the Web is the collection of books, magazines etc. (websites) inside it!