What is blockchain? A visual explanation from a Stanford professor

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.

Watch an expert explain blockchain technology to five different people: a child, a teen, a college student, a grad student, and a fellow expert.

The blockchain offers tantalizing possibilities for future use

Think of blockchains as a running list of information, where new details are added to the running chain as discrete "blocks." With crypto, the information contained within each block could be virtually anything, providing flexibility for uses in commerce, legal filings, healthcare records, and more.

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).

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

The "crypto-" in cryptocurrencies like bitcoin refers to the mathematical functions that generate pairs of public and private keys and encrypt data in blocks. When combined, these systems secure transactions on the network, verify digital asset and token transfers, and contribute to end-user anonymity.

The future of the internet

Blockchain? Crypto? NFTs? Oh my. Gilles DC provides a simple breakdown of what Web3 is, what it involves, its connection with web currencies, and how you can begin your own explorations of this brave new world. Gilles promises to describe Web3 in one take, explain how the reader can take advantage of it, and how blockchain might build a better society as a result.

See how the concept of verification and addition to the blockchain works in real time.

Every transaction made via bitcoin is recorded on its blockchain—the decentralized, distributed ledger that provides a permanent and transparent record of the currency's entire history. While that may sound abstract, the technology allows anyone to monitor and confirm each of the transactions.

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.

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.

The industries ripe for disruption by blockchain and cryptocurrencies

Blockchain—what is it good for? Lots of things, it would seem. Peruse this guide from The Motley Fool site and learn about different applications and use cases for blockchain technology. Financial exchanges, real estate, insurance, voting, an gambling are just a few of the 15 applications discussed here.

Why blockchain applications are worth investing and building

Chris Dixon is a general partner at Andreessen Horowitz. In this hourlong podcast episode, Dixon shares his overall thesis for investing in the cryptocurrency space, the opportunities and limitations of blockchain applications, and why this is the most interesting area for investing and building over the next 10 years.

Princeton University offers a free online bitcoin course

Want to understand bitcoin and cryptocurrencies? A free online course from Princeton University unpacks the details of bitcoin, from how it works to what distinguishes it from other currencies, to the security and anonymity associated with its use. Explore explainer videos, or take the course as a series of lessons.

Learn about Web3 and how it differs from past versions of the internet

Web3 is the idea of a new, decentralized internet built on blockchain technology. It aims to shift control from centralized entities like big tech companies to users through distributed ledgers and smart contracts. Key components include cryptocurrencies, NFTs, and decentralized autonomous organizations (DAOs) that operate without a central authority. Web3 promises more user privacy, ownership, and control over data and digital assets.

Ledgers—what are they good for?

It might seem strange that a ledger—a dull and practical document associated mainly with accounting—would be described as a revolutionary technology. But the blockchain matters because ledgers matter. Read (or listen to) this 14 minute breakdown on why ledgers matter.

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.

Vitalik Buterin explains ethereum in 30 minutes

Every year, ethereum creator Vitalik Buterin explains what his crypto platform is in a 30-minute presentation at the Ethereum Foundation’s event, Devcon. Buterin’s explanation goes deeper than a simple 101 explanation. To learn more about the current state of ethereum, what’s changed recently, and what Buterin expects down the road, watch this video.

Proof-of-work versus proof-of-stake: what's the difference?

The two main consensus mechanisms—the way blockchains confirm and enshrine information—are proof-of-stake and proof-of-work. An overview compares the differences between the two and the latter's ability to reduce the energy intensity of the computation process, which has emerged as one of the biggest criticisms of the crypto boom.

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.

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.

Ethereum is a blockchain-powered operating system known for its cryptocurrency, ether

Ethereum's underlying blockchain allows developers to build decentralized applications (dApps) that leverage smart contracts to seamlessly run decentralized financial tools (crypto wallets, exchanges, marketplaces, and more), along with Web3 concepts like non-fungible tokens.

Explaining the Ethereum merge in simple terms

Ethereum slowly switched the way it adds blocks to the chain. In 2022, it completed its transition from a proof-of-work model to a proof-of-stake model. That event, called “The Merge,” happened when it combined two Ethereum blockchains operating under different systems. For an explanation of proof-of-work and proof-of-stake, and the significance of switching from one to the other, read this article.

The Chain Reaction podcast: The latest in bitcoin and blockchain developments

There are constantly new tokens, DeFi projects, NFT collections, and DAOs being launched, but how can you make sense of everything going on in the crypto space? TechCrunch senior crypto reporter Jacquelyn Melinek explores the impact of crypto on finance, art, web3, and society as a whole. One the best resources to keep up with actual—meaning, beyond the hype—developments in the world of bitcoin and blockchain.

Ethereum is a blockchain-powered platform for building decentralized software and apps

Among crypto enthusiasts, ethereum is known for the cryptocurrency it uses to facilitate transactions: ether, or ETH. It's often compared to an app store. The underpinnings of ethereum's blockchain include dApps, which operate using automated scripts called "smart contracts."

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.

Distinguishing between Web 1.0, 2.0, and 3, all made possible by the internet

The World Wide Web began as read-only, static webpages on Web 1.0, where data could not be entered. With Web 2.0, the online interface became a read-write space for data entry, post creation, and forum participation, among other activities. Web3 is intended to be decentralized, user-owned, and built on blockchain technology.

Four video explainers on quantum fundamentals

Ready to level up your working knowledge of quantum mechanics? Check out these four TED-Ed Lessons written by Chad Orzel, associate professor in the Department of Physics and Astronomy at Union College

Smart contracts are the foundational technology behind NFTs

Smart contracts use “if that, then this” logic to track the ownership of NFTs and record when they are bought and sold on the blockchain.

Decentralized applications are blockchain-based and run without a central authority

These apps use smart contracts to automatically execute functions, ensuring security, transparency, and censorship resistance. Built on platforms like Ethereum, Solana, and Binance Smart Chain, DApps power DeFi, NFTs, gaming, and social media, offering users control over their data and assets.

Read the original white paper from Satoshi Nakamoto

Satoshi Nakamoto's original introductory paper "Bitcoin: A Peer-to-Peer Electronic Cash System," is required reading for anyone who wishes to understand the cryptocurrency. Bitcoin.org provides assorted translations. While Nakamoto's identity remains a mystery, his ideas are neatly laid out here, along with supporting documentation.

An explanation of Turing machines—the foundations of digital algorithms and computers

The device reads data, overwrites or ignores it, and then moves on to the next piece of data based on a set of programmed rules. By imagining this data as zeros and ones—binary that makes up computer code—Turing machines became the theoretical models for how any algorithm could be run on a computer if the procedure could be coded into a set of digital rules.

Netflix, explained

From offering an internet-based, mail-order Blockbuster alternative to its eventual status as a market leader in streaming entertainment, Netflix has led nearly every major paradigm shift in the television and movie business since its inception.

Why cryptocurrency matters from Andreesen Horowitz general partner

In this hourlong video, Andreessen Horowitz (a16z) General Partner Chris Dixon discusses "Crypto Networks and Why They Matter," giving an overview of the cryptocurrency space, the transformative implications of its technology, and the potential for cryptocurrency networks to lead a new wave of innovation.

Quantum physics explained in 22 minutes

Brian Cox, Royal Society Professor for Public Engagement in Science, discusses the fundamental principles of quantum mechanics, emphasizing their importance in understanding the nature of reality and their practical applications in emerging technologies like quantum computers.

The interoperable metaverse and what that means

This explainer video explores the challenges of achieving the interoperability needed to unify economies, avatars and systems across virtual worlds in the metaverse.

Bitcoin started as a .PDF

Have you ever wondered how bitcoin became, well, bitcoin? In this podcast episode, journalist PJ Vogt dives into what drove the bitcoin hype machine, explaining how it became the phenomenon it is today.

The US Mint created a video to show kids how coins are made

The video, made simple for children (or anyone who wants an easy-to-understand 101 video about the process coins go through to get in your wallet), outlines the entire process that a coin goes through in its lifetime, from Congress voting on new coins, to how coins are stamped, to their journey to a Reserve Bank.

Learn how stablecoins function in just 4 minutes

This video explains the basics of stablecoins in a beginner-friendly manner. It also dives a bit deeper into the larger stablecoin landscape, detailing, for instance, the many stablecoins backed by fiat currency other than the US dollar, like the euro, the Turkish lira, and the Singapore dollar.

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."

A fascinating look at how our DNA is built and replicated

This easy-to-understand 13-minute video dives into the wondrous molecule deoxyribonucleic acid – also known as DNA – and explains how it replicates itself in our cells.

Venture firm a16z's crypto canon

Andreessen Horowitz (a16z) is a leading venture capital firm with deep expertise in cryptocurrency and blockchain technology. For 10 years, the firm has built its internal knowledge in the area, and archived a wide range of explainers exploring everything from fundamentals to emerging crypto trends, and much more.

Stanford’s ‘How to Start a Startup’ series

Stanford’s archive of lectures about creating a startup includes advice from Y Combinator notables such as former YC president and OpenAI CEO Sam Altman and YC Cofounder Paul Graham.

How entanglement lies at the heart of quantum computing

Theoretical physicist and mathematician Frank Wilczek boils down the complex notion of quantum entanglement into this reasonably understandable summary. Wilczek discusses the concepts of quantum entanglement and how it relates to other ideas like the Many-Worlds Interpretation (MWI) of quantum mechanics. What sounds a bit "science-fictiony" can have actual real-world and concrete applications.

See how computer memory really works—from binary bits to modern RAM

The video explains how computers store information as 1s and 0s, how RAM functions as fast working memory, and why systems utilize different types of storage. The video demonstrates how this process enables computers to operate.

Visualizing the history of money

Money is any medium of exchange used in payments for goods or services and can take many forms. From cattle and shells in ancient times to paper and blockchain today, money has taken many shapes and sizes. This infographic illustrates some of the major forms of exchange world cultures have used over the last 5,000 years.

In 2008, Satoshi Nakamoto began working on the underlying bitcoin code and blockchain

Widely credited as inventing the currency, Nakamoto abruptly disappeared from the digital world—no one has confirmed his identity, or whether he was even a single individual.

Engineer explains VR at five levels of complexity

While its possible to grab a virtual reality headset and hop into an immersive world with little effort, a significant amount of technical and biological science has gone into creating the effect of a 3D world. This video breaks down the technology in five layers of increasing complexity.

Bank runs, explained

A major feature of the modern financial system is trust: if an institution loses it, customers will quickly withdraw deposits and stockholders will sell their shares. This digestible animated video looks into the nature and history of bank runs and...

Vitalik Buterin’s current thoughts on Ethereum

Vitalik Buterin isn’t just the founder of Ethereum—he’s also a blogger. In this blog post from late last year, Buterin discusses some of his favorite applications built on Ethereum: prediction markets like Polymarket, where users can bet crypto on the outcome of events like elections. Buterin argues that prediction markets also act as news sites for non-bettors, opening the floodgates for many different kinds of info-based apps on Ethereum. Read the post here.

Solana is a blockchain designed for fast, scalable, low-cost transactions

Solana uses a unique Proof-of-History and Proof-of-Stake hybrid to process thousands of transactions per second. Solana supports a wide range of Web3 applications, offering an alternative to Ethereum with lower fees and faster speeds. Its native cryptocurrency, SOL, is used for transactions, staking, and governance.

A simple explanation of semiconductors

Semiconductor chips are electronic devices that store and process information. Today they can contain billions of microscopic switches on a chip smaller than a fingernail. The article provides a quick overview of how the devices work and how they've provided the backbone of the computer age.