What Is the Internet?

The Journey Inside℠, an Intel® Education Program

The simplest definition of the internet is that it’s a network of computer networks. A computer network is a group of computers connected to each other so they can easily communicate and share files and resources (such as printers and scanners). Many organizations and businesses have networks that connect offices all over the country and world.

At its heart, the internet is a backbone of high-speed data communication lines through which any connected computer can trade information with any other connected computer.

One of the most remarkable things about the internet is the wealth of information it puts at your fingertips. It’s an incredible fountain of knowledge fed by sources all over the world. You can find everything from information on the latest cancer research to strategies for beating the latest computer game. The information never stops either. New pages are being added daily. The price of admission? A computer and an internet connection through an Internet Service Provider (ISP), which is a company that provides internet access.

Lesson 1: The World Wide Web

Right now, you’re using a specific part of the internet. It’s called the World Wide Web (or just the web, for short). Until the web was created, the internet was made up of pages that only had text. It didn’t have color or fun graphics of any kind. It was great for scientific reports, government images, or school projects. Consequently, the internet was used primarily by scientists and engineers.

In 1989, Tim Berners-Lee, an Oxford-trained computer scientist, had an idea for a “global hypertext project.” To make his idea a reality, he developed new ways to navigate the internet with a computer language called hypertext markup language, or HTML.

Hypertext is a different way of moving through information. Instead of reading text from beginning to end, you interact with it. You click a link, and suddenly you’re not moving through text from start to finish like you would in a book or magazine article. Instead, you’re making a quick side trip or jump to a new page.

HTML is more than just hypertext though. It’s also a markup language—a system of codes for how a computer should display text and images on a screen. Markup languages also determine how a computer should react to actions you make, such as pressing a key or clicking a mouse button. What made HTML such a perfect markup language for the web is that it can be read by many types of computers and is very economical. It allows web designers to create graphically rich web pages that are small in file size. Small file sizes are important on a network like the web because they are faster and easier to exchange over the thousands of miles often separating computers.

With the creation of HTML, the web was born. HTML made it easy to create websites like this one that have images, videos, and even sound. The small file size allowed them to be quickly shared over the internet. Suddenly, everyone saw the potential of the web as a global communications system and wanted to get on it. The web grew rapidly. Today, billions of people access the web daily for news, entertainment, shopping, education, and business.

Lesson 2: What Is a URL?

Your home has a unique address. That’s why when someone mails you a letter or a package, it shows up right on your doorstep.

Web pages need unique addresses too. These addresses allow you to find a particular page, as well as direct others to it. However, giving each page a unique address is no easy task. The internet is a network of networks, many of which are growing rapidly. In fact, hundreds of thousands of new websites are added daily, each page needing its own address. Fortunately, there are enough parts to a web address that it’s fairly easy to create new ones.

The technical name for a web address is a URL, an acronym for uniform resource locator. Look at the top of your browser right now and you can see the URL for this page. It starts with http://. You’ve probably typed in a URL before to get to a particular web page. Let’s examine each part. We’ll use, for our example, the URL for the website of the National Aeronautics and Space Administration—http://www.nasa.gov.

Try the lesson: Parts of a URL.


Lesson 3: How Information Travels on the Internet Through an ISP

When you connect to a website through an ISP and start exchanging information, there isn’t a fixed connection between your computer and the web server computer that the website is on. Instead, information is exchanged using the best possible path at that particular time. Routers are computers that determine these paths, avoiding slow links and favoring fast ones.

See an example of how information travels on the internet.


Lesson 4: Breaking Messages into Network Packets

A page on the internet—whether it’s full of words, images, or both—doesn’t come to you in one shipment. It’s translated into digital information, chopped into pieces called packets, and sent to you like a puzzle that needs to be reassembled. Web pages are broken down this way because small pieces can travel faster and make the most efficient use of the internet’s resources. Instead of waiting while a long train of information goes by, packets can just fit in wherever and whenever there is space in a wire.

Each packet has its part of the data, plus additional information it needs to be routed to the destination and reassembled with the rest of the packets. Reassembling is important because the packets do not necessarily arrive in the same order in which they were sent. Packets can get jumbled during transmission and occasionally even take different paths. Routers determine the most efficient path at the time the packets enter the internet traffic. This helps prevent traffic jams and makes the internet more efficient. When the packets arrive at their destination, your computer discards the addressing information and puts the packets in the proper order to reassemble the information for you. Once all the packets are reassembled, the complete page appears on your computer screen.

See an example on packets.



Try the lesson: Packing a message.


Lesson 5: Why Bandwidth Is Important

Have you waited a few seconds for a web page to finish loading onto your screen? That could be caused by a combination of many things. First, the file size of the web page may have been very big and there might have been a lot of information to get through. Second, the computer you were using may have a slow microprocessor, a device that processes incoming information in your computer. Third, your connection to the internet may have been slow. For better performance, the connection you were using needed more bandwidth.

Bandwidth is the amount of data that can pass through a particular connection in a set amount of time. It can differ depending on what type of connection your computer has to the internet. The greater the bandwidth of the connection, the faster a web page loads on your screen. Faster bandwidth means files can download faster and videos can play quicker and more smoothly. The more bandwidth your computer has, the better.

See an example of bandwidth.



When the internet was mostly text and fewer people used it, bandwidth wasn’t as important because text pages have small file sizes. But today there are billions more people on the internet, and we use it to exchange photographs, download software, listen to music, and stream movies and videos online. These kinds of files are much larger and require a bigger connection to your computer to perform properly, which is why bandwidth is so important.

Lesson 6: How Bandwidth Is Measured

Bandwidth is a measurement of the amount of information that can be transmitted per second. The unit of measurement used for bandwidth is bps, which stands for bits per second, and is the smallest unit of information handled by a computer. In its digital form, bits represent a 1 or a 0. They don’t mean much by themselves, but groups of 8 bits form bytes that can be used in various combinations to represent letters and numbers.

Today’s connection speeds to the internet are measured in Kbps (kilobits per second) and Mbps (megabits per second):

  • 1,024 bps = 1 Kbps
  • 1,048,576 bps = 1 Mbps

That means a 56 Kbps connection under ideal conditions can transfer 57,344 bps (56 x 1,024 bps) from the internet to your computer. In reality, most 56 Kbps connections transfer around 48,000 bps.

See an example of connection speeds.



How Bandwidth Translates into Speed

At some point, we have all watched a video, read a news article, or played a game online, but have you wondered how large the file sizes for each of those are or how much bandwidth is needed to get that information to you? This activity lets you compare connection speeds to see how much of a difference a fast connection can make when you are trying to do something on the internet.

For reference, look at these different file sizes and what they can do:

  • 3 MB: Listen to a song
  • 5 GB: Watch a video
  • 10 KB–20 MB: Download an image, depending on the resolution
  • 100 KB: Download a PDF

Use the calculator to determine download speed.


Lesson 7: Information on the Internet

One reason the internet has so quickly become a part of our daily lives is you can do practically everything on it. You can listen to music, play games, send messages, shop, and of course, use it to do research and homework.

But how accurate is the information on the internet? While the internet connects us to a boundless amount of fun, enticing, and informative content, there are plenty of cyberthreats, online scams, and unreliable sources out there too.

Anyone can put up a website on the internet. That’s why you have to be careful. There is no editorial review board, no information fact-checker, no quality-control expert. You have to be your own judge on the quality and validity of the information you receive.

You must also be careful when using a search engine like Google or Yahoo!. When you search for something online, every word you type into the search engine is considered a keyword. Additionally, the internet doesn’t show you the pages in an order based on the quality of information, but primarily by where and how often the words in your search appear. Some search engines give extra visibility to pages that have lots of links to them from other web pages. Some give extra visibility to pages frequently clicked on by people doing similar searches. Some search engines even put websites that pay fees in the list of results shown to you.

Search engines are useful, but they may also miss a lot of information. Most have access to less than 1 percent of the content that exists on the web. Billions of pages are not even considered. New, specialized search engines are popping up that focus on specific areas such as news, law, or even shopping. By specializing in a specific area, these search engines answer queries with many pages that traditional search engines would miss.

It’s also important to pay close attention to the source of any information you find on the internet. For example, if you were looking up facts on ancient Egypt, a website created by National Geographic Magazine will be more reliable than a person’s opinion on ancient Egypt or their latest visit to the pyramids. Also make sure to look up multiple sources so you know which facts are correct.

Lesson 8: Staying Safe Online

What can you do to be a savvy web user? Here are some tips to stay safe online.

  • Create strong passwords. Don’t use personal identity information in your password, like your birthday or your phone number. Try using a combination of letters, numbers, and symbols that you will remember—like your pet’s name, your favorite food, your favorite number, and a symbol: BuddyIceCream7!
  • Keep your passwords a secret. Never give out your passwords, except when sharing them with a trusted adult. If someone asks for your password online, do not respond or give it to them.
  • Don’t share your personal information. Never give out personal information like your full name, address, or name of your school.
  • Check your privacy settings. Ask a parent to help you check your privacy settings. They can help you decide what information is shared with others and who is allowed to see your posts.
  • Ask before you post pictures and videos. Get permission from an adult before you post pictures or videos. If other people are in the photo, be sure to get permission from them too.
  • Only connect with friends. Only accept friend or follow requests from people you know in real life.
  • Avoid strangers. Remember that people aren’t always who they say they are online. If someone you don’t know tries to talk to you, don’t respond. If you’re not sure what to do, ask an adult for help.

Lesson 9: Connecting to a Wireless Network

Wireless devices are technologies such as mobile phones, tablets, and notebook computers that do not need to be plugged in with a network cable to access the internet. These types of devices connect to the internet either using a cellular service, often referred to as an LTE connection, or through Wi-Fi at home or in a store.

Wi-Fi is a wireless network that connects computers, tablets, mobile phones, and other devices to the internet. LTE, short for Long Term Evolution, is a type of cell phone service that lets you connect to the internet—for example, to download a game, watch a show, or listen to music—without having to connect to a Wi-Fi network.

The speed at which you connect can vary greatly depending on how close you are to the network antennae or other factors that can interfere with the signal (like walls). Many LTE cellular connections may charge a fee for how much bandwidth you use.