An explanation of TCP/IP, which helps transmit data across the internet like a club sandwich

The internet explained at five levels of difficulty, from protocols to internet flattening

Resembling a roadway with traffic laws that all cars must follow, the internet is the hardware that connects a source to a destination, and these connections must follow specific software rules. Although data had to travel through about 10 networks to reach a destination in the past, data centers increasingly consolidate traffic, just as a highway does for cars, to improve data speeds.

Learn about the protocols that make navigating the internet possible

While TCP/IP sends data in packets to the correct destination and checks for errors, UDP omits such safety features to speed up data transfer for real-time communication and streaming. Software rules such as HTTP and HTTPS enable the transfer of content on the World Wide Web, while SMTP handles email messages between servers.

Onion routing disguises internet traffic in layers resembling a nesting doll

Data is encrypted at least three times before being sent to a node—a server that can only decrypt one layer. Then, the underlying encrypted data is relayed to another node, and the process repeats until all layers are decrypted. Thousands of possible nodes make it extremely difficult to trace activity within the system.

How the Domain Name System works and how it provides a directory for the internet

DNS translates domain names, such as join1440.com, into numerical IP addresses, such as 192.0.2.1, which computer systems use to determine what content a user is looking for across the World Wide Web, making navigation easier for the vast majority of users. Web outages can occur if the DNS servers making these translations become inaccessible.

An overview of the World Wide Web, which is often confused with the internet

When users create a website, they organize content and store it on a web server—one of various types of hardware that make up the internet—in web languages, such as HTML and JavaScript. When visiting the site, a web browser translates these languages into text and other media for consumption.

The 500 subsea cables that run the internet

Subsea cables carry the majority of data sent across the globe on the internet. An estimated 552 such cables—with more in development—lay on the ocean floor, their thickness similar to a garden hose, made up of optic fibers covered in copper.

View the ecosystem of global services, organizations, and agencies behind the internet

Through an open, transparent, and collaborative model built on open standards development and shared global ownership, the internet is kept freely accessible amid evolving international policies. Key organizations, such as IANA, which allocates IP addresses and fulfills administrative functions for the Domain Name System, function as non-profit organizations.

The Internet of Things connects everyday objects to the internet

The IoT enables physical devices to share data collected via sensors or specialized software, often without human intervention. Controlling the air conditioning and heating in one's home via an app, as well as receiving alerts when away from home about someone at the door, is made possible by the IoT.

Transistors are the foundation of electronic signal processing

Small amounts of voltage can allow or block the flow of electrons across a transistor made from modified layers of semiconducting materials. The conducting (1) and insulating (0) states can be quickly modified as binary code is processed in a computer system.

What is Net Neutrality?

ISPs shouldn’t be able to block some sorts of data and prioritize others. Here’s what to know about the struggle to treat all information on the internet the same.

View the layout and components that make up a typical data center

Alongside server rooms for the storage, processing, and transmission of data, data centers include climate control systems to manage the heat generated by microchips, backup systems to ensure systems can run during power outages, offices for on-site personnel, and monitoring and security stations to provide continuous protection against physical threats.

The reflection of light within a material is the basis for fiber optics

As light travels from one material to another, it can be absorbed, reflected, or transmitted through, depending on the properties of the two materials. Fiber optic cables are designed to reflect light internally, minimizing data loss as information is sent at high speeds through flashes that represent zeros and ones.

Married computer scientists at Stanford University built the router that became the foundation for Cisco

Len Bosack and Sandy Lerner were both computer scientists at Stanford University in 1984 when the pair created a router that connected computers on different networks. The pair asked for Stanford's permission to manufacture the router, but the university declined, and the couple decided to leave their jobs to launch Cisco, one of the tech companies that powers the internet.

Explaining computer kernels and what makes monolithic kernels different from microkernels

A kernel is an intermediary piece of software on a device that manages the connection between software programs—the services and processes they perform to run correctly—and the available hardware resources, such as memory and computing bandwidth, including prioritizing resource allocation and managing access to specific hardware. A monolithic kernel manages all of an operating system's services, whereas a microkernel only handles essential services.

Watch a video that visualizes what really happens inside a credit card network when you make a purchase.

Every tap sets off a lightning-fast relay. When someone buys coffee with their Visa, a tiny "runner" races between the coffee shop's bank, Visa's network, and their bank—all in under a second. The catch? No money has actually moved yet. Here's what really happens behind that instant "Approved."

Ads follow you around the internet through cookies

A technology called “cookies” enables advertisers to essentially team up and follow your behavior around on the internet. This video explains why it seems like ads seem to follow you as you go from website to website—as well as data privacy advocates’ war against cookies.

How Model Context Protocol allows AI systems to communicate with databases

Developed by Anthropic, the open-source software serves as an integration layer that standardizes how large language models connect to real-time information sources or tools. Just as a USB-C port serves as a universal standard for many peripherals, MCP streamlines these integrations and provides context about external sources to LLMs in a way that AI can understand.

Understanding the Diffie-Hellman key exchange, an example of public key cryptography

Published in 1976 by Whitfield Diffie and Martin Hellman, the system involves two parties combining each of their unique private keys with a public key using a mathematical function. The combinations are exchanged and mixed to establish a common key that no third party can determine. The Diffie-Hellman system underlies many encryption protocols for internet traffic.

What is the immune system? A quick 101

Your body’s immune system is designed to protect you from infection. Find out more about how the immune system works with this quick overview and set of diagrams.

Understanding the basics of football

While American football may be entertaining, for fans who never played the game it can be confusing. Why do teams choose to run, pass, line up in certain defenses, run people in motion, call audibles at the line—or do any of the many other things that happen on the field?

What is blockchain? A visual explanation from a Stanford professor

Stanford professor Dan Boneh teaches “Blockchain Primitives: Cryptography and Consensus,” providing an introduction to the cryptographic foundation of blockchains and how developers can use them to build new types of applications.

A simple pictorial explanation of ocean geography

Visualizing ocean geographical features, such as a coastal zone, continental shelf and abyssal plain. This article from the US Geological Survey also provides several links to diverse ocean facts.

Breaking down the main classes of intellectual property: trademark vs. copyright vs. patent

Trademarks, copyrights, and patents are all intellectual property classifications that give exclusive ownership of ideas and concepts to individuals or businesses. Patents usually refer to innovative products or processes, copyrights are centered around the right to reproduce content, and trademarks usually involve branding elements, like names, logos, and distinct product elements.

20 of the most common cyberattacks

While there are dozens of different types of cyber attacks, this article explains the top 20 most common network attack examples, including phishing, whale-phishing, and spear-phishing attacks. Learn how to best protect yourself.

A breakdown of Earth's atmospheric layers, including why it can get colder or hotter with altitude

Gases in the troposphere—the atmosphere's lowest layer—cool with increasing height as they get farther from the thermal energy emitted by Earth's warm surface. In the next layer—the stratosphere—ozone is increasingly heated by the sun's ultraviolet radiation with height. Because cooler air sinks and hotter air rises, the cooler troposphere and hotter stratosphere form a natural boundary keeping Earth's weather in the lowest layer.

Chaos theory—informally known as the butterfly effect—is the reason why weather forecasts are presented with probabilities rather than certainties.

The name 'Silicon Valley' arose from the founding of Shockley Semiconductor Laboratory in Fairchild Semiconductor in 1956-57, founded near Stanford University in Palo Alto

When you complete a CAPTCHA on a website to prove you are human, you may be unknowingly training algorithms for self-driving cars, whose systems require training data to help identify crosswalks, bicycles, and other outdoor objects.

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

How Amazon operates a 'flywheel' business model, a self-reinforcing cycle that drives continuous growth

Hear about the 250-year history of the United States Postal Service, complete with some of its strangest deliveries, important innovations, and the figures that made it an American institution.

Visualize how CRISPR-Cas9—a type of immune system used by single-celled organisms to attack invasive viruses—targets and makes precise changes to a gene's DNA.

Netflix profits when you're not watching, and its movies are designed that way—read a detail-rich critical essay exposing lesser-known Netflix takes

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

The United States is one of only around two dozen countries with a fully federal system of government, in which power is divided between national and state governments.

Learn how your body is, scientifically, like a firework with its own slow, controlled burn.

According to the physics of black holes, our 4D reality may be a hologram—a projection of information coded on a 2D surface on the edge of the universe.

All rainbows are 'raincircles' caused by water droplets separating white sunlight into a spectrum of colors, but Earth's surface blocks the bottom half of the circle from our line of sight.

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

Ebola is a filovirus, meaning it resembles a thread under a microscope, though it sometimes twists and can resemble a bowl of spaghetti.

An initial public offering or 'IPO' is the process of a private company becoming public by putting shares of the company on the stock market for purchase.

Power lines are dotted with large, brightly colored balls to improve the visibility of these thin wires to helicopters and small planes and help prevent potential crashes.

The American Society of Civil Engineers' infrastructure report card gave the US a C in 2025, its highest grade since the project launched in 1998.

The American cockroach is actually from Africa, an apparent hitchhiker aboard ships carrying enslaved people, with evidence suggesting the bug may have arrived in the New World as early as the 1600s.

The price of gas is a composite made up of several different factors, with the federal gas tax making up less than 20% of what drivers pay at the pump.

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

Explore the animals that populate the depths of the ocean, from fish and coral in the first few hundred feet, all the way down to the bottom of the Mariana Trench.

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

SpongeBob exemplifies Aristotle's philosophy for living well because he understands that happiness doesn't come from external factors like money, recognition, or power.

The word 'jazz' evolved from 'jasm,' 19th-century American slang for 'energy'