A visual guide to how bitcoin transactions work and rely on cryptography

A definitive guide to crypto and blockchain

The concept of cryptocurrency emerged more than a decade ago, with a famous whitepaper on bitcoin. To fully understand the rise of bitcoin, Bloomberg’s Matt Levine developed this comprehensive four-part series exploring the broader crypto and blockchain ecosystems, where they came from and how they work (subscription required).

Bitcoin explained and made simple

Bitcoin, the most popular and well-known example of a cryptocurrency, came on the scene around 2010, with its evangelists proclaiming it would eventually displace government-backed traditional cash. While the concept of a digital currency may seem straightforward, the details can be deceptively simple. This quick video overview provides the foundation for a deeper dive into the world of decentralized currency.

A simple visual explanation of how blockchains work

Blockchains are decentralized, distributed, and digital methods to record transactions and prevent alterations and tampering of the record. That's a simplified definition. This easy-to-understand six-minute video further and better explains what blockchains are and how they work using colorful illustrations and clear, concise clarifications on their processes and what makes them so special.

A look at nodes and miners in managing bitcoin transactions

Each time a transaction involving bitcoin is carried out, the information must be relayed and recorded onto the currency’s blockchain. Multiple steps are involved, including the passage of the transaction to various nodes and miners who comprise multiple layers of verification and validation. See an illustrated guide to how these two crucial features of bitcoin processing work here.

Using cryptocurrency to turn traditional financial arrangements on their head

Cryptocurrency is poised to drastically change everything in the financial world, including financial arrangements. Decentralized finance makes it easier for virtually anyone to take advantage of financial markets without the need for a bank. However, there are new risks involved as well. Professor of Legal Studies and Business Ethics Kevin Werbach, an expert on Bitcoin and blockchains discusses it all in detail in The Conversation.

The benefits of cryptocurrency and blockchain technology

At the root of cryptocurrencies' allure is blockchain technology, an innovation bringing profound transformations to industries, especially the financial industry. This simple article breaks down the difference between cryptocurrencies and blockchain as well as the benefits of each.

Cryptocurrencies are forms of digital currency

Cryptocurrency's key feature is decentralization. Unlike traditional money, they generally aren't controlled by a single authority. As of early 2025, cryptocurrencies had a cumulative market cap of almost $3.4T, making them worth more than some of the world's most valuable companies, like Google and Amazon (both valued at roughly $2.3T).

Visualize how passkeys, which rely on asymmetric cryptography to authenticate users, work

After using biometrics or a PIN to access the private key stored on a device, it is combined with a random number generated by the site to produce a cryptographic signature. This signature is verified using the site's public key, allowing a user to log in without entering a password. This reduces the risk of fraudulent messages—phishing attacks—and data breaches.

Crypto exchanges are online platforms to buy, sell, and exchange cryptocurrencies

Crypto exchanges have grown alongside and fueled the boom in digital currencies. Popular exchanges like Coinbase, Kraken, and Binance each have separate features, fee structures, and more. You can learn how to begin with the platforms, how to carry out research, and when to be aware of the associated risks.

The science of cryptography, including methods to encrypt data and how to break encryption

Monoalphabetic ciphers use a set of rules to replace each letter with another consistently, making them susceptible to brute force attacks that try every kind of replacement. While more complex ciphers can transform text in less obvious ways, because certain letters are used more often than others, an analysis of letter frequency may reveal patterns that help uncover the rules that make up a cipher.

What are smart contracts?

Smart contracts are potentially one of the most useful tools associated with blockchain, and they can enable the transfer of everything from Bitcoin and fiat currency to goods transported around the world. Here’s what they do and why they’re likely to gain traction.

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.

Proof-of-work is the original way cryptocurrencies added new blocks to blockchains

It’s a competitive method requiring “miners” to solve cryptographic puzzles, often using equipment that consumes massive amounts of energy. Ethereum switched to proof-of-stake, a less energy-intensive method in which “validators” stake crypto to be randomly chosen to check transactions.

The role stories play in mass economic trends like bitcoin, crashes

Economics is dominated by numbers, but stories play a huge role in the emotional shifts seen within macroeconomic trends. For example, bitcoin is not just a cost-benefit winner, but a compelling tale of decentralization and independence. This is a 20-minute summary of Nobel prize-winning economist Robert Shiller's "Narrative Economics."

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."

Memecoins are a type of cryptocurrency—a form of digital currency with a wide variety of uses—created around popular 'memes,' or viral internet jokes.

The cryptocurrency equivalent of going public

An initial coin offering (ICO) is cryptocurrency's version of an initial public offering (IPO). Similar to the way a company offers shares on the stock market for the first time, ICOs occur when a cryptocurrency company seeks to raise funding for a new coin, app, or service. If you're entering the field, get the details on how it all works.

Explore a visual guide to how quantum computers can crack RSA encryption

In 1994, Peter Shor introduced an algorithm that showed a quantum computer could efficiently factor the product of two very large prime numbers, undermining the mathematics that makes RSA so secure. While using larger keys can delay the decryption time of quantum computers, this solution increases the time it takes to encrypt data, which may become impractical.

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.

Making sense of the parts of a check

Though individuals use checks sparingly if at all, half of businesses rely heavily on check-writing to pay suppliers and contractors. Get to know the parts of a check with this visual guide.

The acronym NFT stands for non-fungible token

NFTs have developed as a secure way to use cryptocurrencies and the blockchain to create unique digital art, allowing the owner to prove ownership of a specific digital item.

Binary mathematics represented as switches allows silicon rocks to do math

Each switch is assigned a zero or a one based on whether it is open or closed, and logic gates are built from these switches that let the system perform mathematical operations. Modern software builds upon these operations to perform increasingly complex tasks.

A breakdown of algorithms, how they are constructed, and their applications

Algorithms are instructions for accomplishing a goal and typically take the form of a step-by-step procedure. Given the conditions, these procedures can take various paths, increasing an algorithm's complexity. While traditional computer algorithms are programmed to account for all possible scenarios within a given process, machine learning systems build their own rules from data-driven patterns.

An interactive guide to the cardiovascular system

The cardiovascular or circulatory system moves blood throughout the body, ensuring cells have necessary nutrients and removing any waste. Click through this interactive 3D guide to explore the system as it crisscrosses the body via arteries, veins, and capillaries. This guide also includes similar breakdowns of the body and its other processes.

A mathematical and visual analysis distinguishing chaos from randomness

Random systems lack any underlying pattern or causal relationships, while chaos is mathematically deterministic because the behavior follows established laws of nature. In 3D plots, chaotic systems produce outputs that approximate a mathematical function, while random points appear as statistical noise.

Visualizing cyberattacks by country

Cyber crime is expected to cost the global economy trillions per year by 2025. This data illustration showcases the countries with the most severe cyber attacks from 2006-2020.

Some coin denominations have ridges etched on their sides, partly to prevent counterfeiting, in a practice called 'reeding.'

Watch this video that uses Lego bricks to explain how venture capital works.

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.

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.

The US dollar is the most widely circulated currency in the world, and is involved in nearly 90% of global transactions

Learn how to read a prospectus, the juicy document that any company must file with the SEC before going public.

The term 'algorithm' originated from the Latinized name of al-Khwārizmī, a 9th-century mathematician whose works introduced Arabic numerals and the decimal-based numeral system to Europe and whose treatise 'Al-Jabr' gave algebra its name.

Art theft is the third-largest source of criminal revenues worldwide, thanks in part to the subjective nature of valuing a work of art.

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.

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

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

See how fireworks are made and learn how metals like magnesium and copper are responsible for different colors.

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.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Explore the known asteroids, comets, and spacecraft involved in asteroid studies within our solar system with 'Eyes on Asteroids,' a 3D visualization from NASA.

The first steps to rebuilding your credit score include getting to know exactly what's on your credit report and figuring out how far you are from the '700 club,' or 'good score' range.

Warren Buffett's former professor Benjamin Graham is known as the 'father of value investing,' a strategy in which investors seek to buy stocks trading below their intrinsic worth.

Fear or disgust related to clusters of holes and cracks, called trypophobia, may stem from evolutionary processes to help us avoid pathogens.

Corals are themselves not coral reefs—the term refers to the tiny marine invertebrates that build the rigid reef.

Alzheimer's can lead to brain shrinkage, with an average of around 2% of volume reduction per year

Calculate how much of your tax dollars go to each federal program based on your income, filing status, and number of children

The rivalry between Alexander Hamilton and Thomas Jefferson centered on federalism—the question of how much power the federal government should hold relative to the states.

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.

Iran's Revolutionary Guard Corps is independent of Iran's regular army and is one of the most powerful and influential military-political organizations in the Middle East.