How Does the Internet Work?

Explore the past, present, and inner workings of the internet to learn how it works.

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Last Updated: Sep 5, 2024
A graphic design of various internet-related devices and equipment.
The internet has been around for a long time, but how exactly does it work?

The internet seems like this incomprehensible thing that allows us to share information at the speed of light. That’s a nearly accurate description, but the internet isn’t impossible to understand. It was created by humans, so we have a solid understanding of what it is, how it works, and what it can do. Curious about the inner workings of the technology that’s a crucial part of our everyday lives? Here’s everything you need to know about how the internet works.

What Is the Internet?

A graphic-design image of binary numbers traveling to and from computers.
The internet is all about data exchange.

The internet is a web of interconnected computers sending and receiving information. Computers and similar devices are designed to communicate with each other to form connections made up of packets of information. Those connections comprise the interactive network we know as the internet.

The nature and infrastructure of the internet can be difficult to understand on its own. That’s why many tech experts and computer engineers use metaphors to describe the internet and its functions. The “World Wide Web” was one of the first metaphors to describe the size and structure of the internet.

Before the advent of the internet, words like “cyberspace” and “website” didn’t exist. No internet metaphor is perfect, but it may be helpful to think of the internet as a large system of roads. Highways and interstates connect smaller streets and roads to the broader system. The entire system is governed by various organizations at the local and national levels, but no international body controls the entire system.

Information acts like vehicles, moving from one point to another via the network of roads. Even if a road is closed or needs repair, the flow of traffic can be rerouted via an alternate path. As the population grows, more roads can be added, ensuring that the system is constantly growing and improving.

Most homes and businesses are connected to the road network by driveways, much like homes or businesses are connected to the internet via local networks. Whenever you want to access the road (internet), you can easily turn on your car (device) and join the rest of the traffic. In doing so, you can gain access to everything that is connected to the road (internet).

A Brief History of the Internet

A timeline detailing important events since the creation of the internet.

The internet we know today isn’t exactly the same as it was when it was created. It continues to grow very rapidly. In the beginning, it connected just two networks. Today, there are millions of networks and devices sharing information across the internet.

How Does the Internet Work?

The road and highway metaphor may give you a better idea of the internet as a whole, but it doesn’t really tell you how it all works. Two fundamental terms you should know: packets and protocols. Once you understand those two concepts, you can better comprehend how the internet functions.

What Are Packets?

When computers exchange information, every message contains a packet or part of a message. The header of a packet contains information about the packet’s contents. It goes at the front of the message so the device receiving the message knows what to do with it.

When one device sends information to another device, the entire message is broken down into packets, which are then broken down into bits. A bit is the smallest measurable unit of digital information, and it can be represented by a one or a zero. The bits and packets get routed to their destination, where they are reassembled in their original format.

Computers use a two-symbol language known as binary code to speak to one another.

Packets are sent through a process known as packet switching, in which routers and switches process packets before they arrive at their destination. That technique ensures that no connection takes precedence over another in the larger network.

What Are Protocols?

In computing, a protocol is a standardized way of doing a certain action or formatting a piece of information. Since there are thousands of kinds of devices running different systems, the internet must be compatible with all of them. Protocols ensure that any internet-ready device can connect to the network. It’s important to note, however, that there are different protocols for different purposes. Two of the most important ones to know are internet protocol (IP) and transmission control protocol (TCP).

What Is Internet Protocol (IP)?

The IP is responsible for delivering packets from one device or network to another. When you have two different devices or systems connecting to the internet, you need a way to translate the information for each network. Every network is assigned an IP address, while every packet contains information (in the header) that says what it is, where it’s coming from, and where it’s going. The IP ensures that every packet can be read, disassembled, relayed to the correct location, and reassembled.

The IP is very similar to any process you may use when sending or receiving an item. If you want to mail a package to your friend, for example, you’ll need to put it inside a box or envelope that complies with standardized sizes set by the post office. You’ll also need to put down the relevant information of the sender (you) and the recipient. If you put down the information in the wrong place or the wrong order, your package likely will end up in the wrong place.

The IP works in much the same way. Every packet must have the right information so different routers and switches can interpret where it is coming from and where it is going, making the IP an essential component of the internet.

What Is Transmission Control Protocol (TCP)?

The TCP works in tandem with the IP to ensure that packets are sent correctly between networks. Whenever a packet is sent, the TCP first reads the header of the packet and creates a connection with the recipient. The TCP then works to make sure the contents of the packet — known as the payload — arrive at their destination in the correct order.

Using TCP, the recipient network must acknowledge receipt of every packet. If the TCP does not have receipts for certain packages, they will be resent. Missing packets can slow down the process.

Returning to the metaphor of sending a package, the TCP is much like a processing or distribution center. Packages and letters arrive at the facility, where they’re sorted and routed to the correct location. If information is in the wrong place or missing, it may delay the process.

How Does a Network Work?

Now that you have a better understanding of the processes that connect multiple networks, you may be curious about how your home network — or any network — actually works. A computer network requires some kind of node to exist. A node is any device that can send, receive, or forward information. That could be a computer, server, switch, smartphone, smart TV, or smart-home device. Each node in a network uses a unique address, such as an IP address, to communicate with other nodes.

To connect to the internet, a network must interface with an internet service provider (ISP). That connection can be established through various means, depending on the type of service and technology available. Wired connections include fiber optic, DSL, and cable internet, while wireless connections refer to satellite, fixed wireless, and 5G home internet.

Routers manage the communication between different networks. They analyze the data being sent and determine the best path for it to reach its destination. Routers connect your home network to the internet (which comes from a modem) and manage the data traffic between your home devices and the outside world. They use various routing protocols to ensure that data packets are delivered efficiently and accurately.

Types of Internet and How They Work

A graphic design image depicting the different types of internet connections.
There are six primary internet connection types available.

There are different types of broadband connections available, each varying in how they supply internet to homes. That includes wired internet options such as fiber optic, DSL, and cable, as well as wireless options, such as satellite, fixed wireless, and 5G home internet. Each type has its own method of transmitting data, which affects speed, reliability, and availability.

How Does Cable Internet Work?

Cable internet uses the same coaxial cables that deliver cable television services to provide internet access. The ISP sends data signals through the cables, which are capable of carrying a wide range of frequencies. In your home, a cable modem receives the signals and converts them into a form that your computer and other devices can use. The modem is connected to a router, which then distributes the internet connection to various devices either wirelessly or through Ethernet cables.

The data transmitted via cable internet is managed through a system called Data Over Cable Service Interface Specification (DOCSIS), which allows for high-speed data transfer and efficient use of bandwidth. Because cable internet operates on a shared network, however, the bandwidth is divided among multiple users in the same geographic area. That means internet speeds can fluctuate depending on the level of usage in the local network, often slowing down during peak times when many people are online simultaneously. Cable internet remains a popular choice due to its wide availability and generally high-speed capabilities.

How Does Fiber Internet Work?

Fiber internet transmits data as light signals through strands of glass or plastic fibers, which are bundled together in fiber-optic cables. Fiber-optic cables can carry data at much higher speeds and over longer distances than the traditional copper cables used in DSL or cable internet — and with minimal signal loss. At the source, the ISP converts electronic data signals into light pulses, which travel through the fiber-optic network to reach your home. Once there, an optical network terminal (ONT) converts the light signals back into electronic data that can be used by computers and other devices.

The primary advantage of fiber internet is its ability to provide extremely high bandwidth, allowing for faster upload and download speeds, lower latency, and greater reliability than other types of internet connections. That makes fiber internet particularly suitable for bandwidth-intensive activities such as streaming high-definition video, online gaming, and supporting multiple devices simultaneously.

How Does DSL Internet Work?

DSL (digital subscriber line) internet transmits data over traditional copper telephone lines. Unlike dial-up internet, which also uses telephone lines but ties up the line for phone calls, DSL operates on frequencies that don’t interfere with voice communication, allowing you to use the internet and make phone calls simultaneously. An ISP sends data signals through the telephone lines to a DSL modem in your home. The modem then decodes the signals and provides an internet connection that can be used by computers and other devices through a router.

DSL internet speeds are typically slower than those offered by cable or fiber-optic connections, but they’re sufficient for many standard internet activities such as browsing, emailing, and streaming video. The speed and quality of a DSL connection can vary based on the distance between your home and the nearest telephone exchange or central office. The closer you are to the exchange, the better the connection will be. DSL is a widely available and reliable option for internet access, particularly in areas where cable and fiber-optic infrastructure are not yet established.

How Does Satellite Internet Work?

As the name implies, satellite internet uses satellites orbiting the Earth to provide internet access, particularly in remote or rural areas where traditional wired connections are unavailable. The process begins with an ISP sending data to a satellite in geostationary orbit. The satellite then relays the data to a dish installed at your home. The dish, mounted on the roof or in an open area with a clear line of sight to the sky, captures the signal and transmits it to a modem inside the home. The modem then converts the signal into an internet connection that various devices can use.

Satellite internet can cover vast geographical areas and provide connectivity where other types of internet are impractical, but it often suffers from higher latency due to the long distance the data must travel between the Earth and the satellite. That latency can cause noticeable delays, particularly in video calls and online gaming. Satellite internet speeds can also be affected by weather conditions and physical obstructions. Advancements in satellite technology are continually improving the reliability and performance of satellite internet services.

How Does Fixed Wireless Internet Work?

Fixed wireless internet transmits data through radio signals between two fixed points: a base station and a receiver installed at your location. The base station, operated by an ISP, broadcasts a signal to a fixed antenna or dish mounted on your home or property. The receiver captures the signal and transmits it to a modem inside the home, which then converts the signal into an internet connection that can be used by various devices, either directly or via a router.

Fixed wireless internet is useful in rural or underserved areas where traditional wired connections, such as DSL, cable, or fiber, are unavailable or cost-prohibitive to install. It can offer high-speed internet access with relatively low latency compared to satellite internet, because the data does not have to travel as far. The quality and reliability of the connection, however, can be affected by physical obstructions such as trees, buildings, and terrain, as well as weather conditions.

How Does 5G Home Internet Work?

5G home internet uses the fifth generation of wireless technology to provide high-speed internet access to homes, using cellular networks to deliver data. An ISP sets up 5G towers that emit high-frequency radio waves, which are received by a 5G modem or router installed in your home. The modem converts the radio signals into an internet connection that can be used by various devices, either wirelessly or through Ethernet cables.

The primary advantage of 5G home internet is its potential for extremely high speeds and low latency, making it suitable for bandwidth-intensive activities such as streaming 4K video, online gaming, and supporting multiple smart devices simultaneously. Because 5G doesn’t require extensive physical infrastructure like cables or fiber optics, it can be deployed more quickly and is considered more cost-effective, especially in areas where laying traditional internet cables would be challenging.

The performance of 5G home internet, however, can be influenced by factors such as network congestion, distance from the 5G tower, and physical obstructions, but ongoing advancements in 5G technology aim to mitigate those issues and improve overall service reliability.

Internet vs. World Wide Web

The internet and the World Wide Web (WWW) are often used interchangeably, but they refer to different aspects of digital connectivity. The internet is the global network that provides the foundation for various services, while the World Wide Web is one of those services, specifically focused on accessing and sharing web-based content.

The internet is a global network of interconnected computers and other devices that communicate using standardized protocols such as IP or TCP. It serves as the underlying infrastructure that allows for various forms of digital communication, including email, file transfer, online gaming, and streaming services. The internet is a vast network that connects billions of devices worldwide, enabling them to exchange data.

The World Wide Web is a system of interlinked hypertext documents and multimedia content accessed via the internet. Developed by Tim Berners-Lee in 1989, the WWW operates through web browsers such as Chrome, Firefox, and Safari, which retrieve and display web pages from web servers. The WWW uses the HTTP/HTTPS protocol to facilitate the transfer of web pages, which are often written in HTML and can include text, images, videos, and other multimedia elements.

Using the road analogy, imagine the internet as an expansive system of interconnected highways that span the globe, facilitating the movement of various types of vehicles (data packets). The highways represent the physical infrastructure and pathways through which data travels between different locations worldwide. The WWW is a specific system of interconnected roads and streets within cities and towns, lined with buildings (websites) that contain information. Just as highways are part of a larger transportation network that includes local roads and streets, the WWW is a subset of the internet, focusing specifically on accessing and navigating web pages and multimedia content through web browsers.

Frequently Asked Questions About Internet

Who runs the internet?

The internet is a decentralized network of networks that is not owned or controlled by any single entity or organization. Instead, it operates through a collaborative effort involving numerous stakeholders, including governments, private companies, nonprofit organizations, and academic institutions. Those entities work together to develop and maintain the technical standards, protocols, and infrastructure that enable the internet to function globally.

Is the internet physically connected?

Yes, the internet is physically connected through a vast network of cables, fiber optics, and wireless transmission systems that span the globe. The physical connections, often referred to as internet backbone networks, link thousands of networks operated by internet service providers, telecommunications companies, and other organizations.

What keeps the internet going?

The distributed nature of the internet, with its multiple pathways, ensures that if one part of the network fails or experiences congestion, data can reroute through alternative paths. Continuous investments in infrastructure by ISPs, telecommunications companies, and technology firms maintain and expand the physical networks that comprise the internet backbone.

Could the internet be shut down?

The internet is highly resilient due to its decentralized and distributed nature, making it extremely difficult to completely shut down worldwide. Localized disruptions, however, can occur due to natural disasters, infrastructure failures, cyberattacks, or government actions such as censorship or shutdowns of specific services or networks within their jurisdiction.