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A source-led Web3 path: foundations first, then the mechanics those ideas depend on, then markets, DeFi, and advanced infrastructure.
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Start here
Six foundational articles. Read these before the rest of the path.
- What is a blockchain? A blockchain is a way for many participants to keep and verify one shared history of state changes without a single trusted operator. Here …
- What is cryptocurrency? Cryptocurrency is a broad label that gets applied to native network assets, application-issued tokens, and stablecoins alike, even though t…
- What is a crypto wallet? Despite the name, a crypto wallet does not literally hold coins the way a physical wallet holds cash. It holds the signing authority that c…
- Bitcoin Bitcoin is a peer-to-peer electronic cash system proposed in 2008 by the pseudonymous Satoshi Nakamoto and brought online in 2009. The whit…
- Ethereum Ethereum is a programmable blockchain first proposed by Vitalik Buterin in a draft circulated in late 2013, with the canonical whitepaper p…
- Solana Anatoly Yakovenko proposed Proof of History (PoH) as a way to verify order and the passage of time between events. The project’s whitepaper…
Start here / Foundations
Shared-ledger mental models, then wallets and keys, then the three networks most later articles assume.
- What is a blockchain? A blockchain is a way for many participants to keep and verify one shared history of state changes without a single tru…
- What is decentralization? "Decentralized" gets applied to blockchains, applications, and organizations as if it meant one simple thing. In practi…
- What is cryptocurrency? Cryptocurrency is a broad label that gets applied to native network assets, application-issued tokens, and stablecoins …
- What is Web3? Web3 is used to describe everything from a specific blockchain vision to a general marketing label. Here is the term's …
- What is a crypto wallet? Despite the name, a crypto wallet does not literally hold coins the way a physical wallet holds cash. It holds the sign…
- Private key A private key is secret cryptographic material, often 32 bytes, that forms the secret half of a cryptographic key pair;…
- Seed phrase A seed phrase, also called a recovery phrase or mnemonic, is a human-readable encoding of high-entropy random data. In …
- Bitcoin Bitcoin is a peer-to-peer electronic cash system proposed in 2008 by the pseudonymous Satoshi Nakamoto and brought onli…
- Ethereum Ethereum is a programmable blockchain first proposed by Vitalik Buterin in a draft circulated in late 2013, with the ca…
- Solana Anatoly Yakovenko proposed Proof of History (PoH) as a way to verify order and the passage of time between events. The …
- Smart contracts Nick Szabo used “smart contract” in the mid-1990s for computerized protocols that carry out contractual terms. On today…
- Gas fees Resource metering exists so that execution cannot loop forever, storage cannot grow without cost, and block space is ra…
How blockchains work
Nodes, pending transactions, settlement, consensus, and the account or token models used on Bitcoin, Ethereum, and Solana.
- What Is a Blockchain Node? A node is an instance of client software connected to peers. It is not a wallet, not an account, and not automatically …
- What Is a Mempool? A mempool is a node’s local set of valid-looking transactions that are not yet in a block. It is not a single global qu…
- What Is a Nonce in Crypto? A nonce is a context-specific value used to vary, order, or prevent reuse of a cryptographic message. The important que…
- What Are Block Confirmations? A transaction is unconfirmed while it sits only in mempools. It has one confirmation when it is in a block that your no…
- What Is Finality? Finality is a claim about how hard it is to replace a block once the network has accepted it. Probabilistic finality (B…
- What Is a Blockchain Fork? Fork has three related but distinct meanings: Competing-chain fork. Different valid blocks extend the same parent. A ne…
- Proof of work Bitcoin uses a Hashcash-style proof of work so that a peer-to-peer network can agree on a single history without a mint…
- What Is Bitcoin Mining? Mining combines two related jobs: Block construction: choose valid transactions, order them, create a coinbase transact…
- What Is a Bitcoin Halving? A Bitcoin halving is a consensus-enforced reduction in the block subsidy. The subsidy began at 50 BTC per block and ste…
- Proof of stake Proof of stake (PoS) is a family of consensus designs that select block producers and voters according to stake ownersh…
- Validators “Validator” is a role, not one machine design. On Ethereum it is a protocol object with a 32 ETH activation minimum, an…
- Staking Native staking commits a network’s own asset to consensus, through rules that may use bonded locks or delegated stake o…
- Account Model vs UTXO In Bitcoin’s UTXO model, every input points to a specific unspent transaction output. A valid transaction consumes each…
- What Is the EVM? The EVM is Ethereum’s deterministic execution environment. Given valid pre-state and a transaction, it executes message…
- What Is an ERC-20 Token? ERC-20, standardized as EIP-20, defines an interface for fungible-token contracts.
- What Are SPL Tokens? SPL refers to the Solana Program Library, and Solana documentation calls assets managed by its Token Programs SPL token…
- What Is a Block Explorer? A block explorer usually has three layers: Node or RPC access supplies protocol data such as blocks, transactions, rece…
Using crypto safely
Custody choices, signing surfaces, and the common ways a wallet or approval is abused.
- Self-custody Custody, in this setting, is the practical ability to authorize a transfer. On typical public blockchains that means co…
- Hot Wallet vs Cold Wallet Hot wallet describes a signing setup in which key material is stored or usable on a network-connected computing environ…
- What Is a Hardware Wallet? Hardware wallets usually generate or import secret material, derive account keys, and perform signature operations with…
- What Are Token Approvals? Under ERC-20, approve(spender, value) sets how much spender may withdraw from the caller, allowance(owner, spender) rep…
- What Is Address Poisoning? The attack combines three things: public transaction activity that reveals addresses a target uses; an attacker-control…
- What Is Multisig? An M-of-N threshold names the minimum approvals M accepted from N authorized keys. A 2-of-3 policy tolerates one unavai…
Markets & token economics
Venue structure, supply figures, valuation labels, and the asset types those numbers are applied to.
- CEX vs DEX “CEX” and “DEX” describe market structures, not safety ratings.
- Circulating vs Total vs Max Supply Total supply is current issuance, commonly net of units the chosen methodology recognizes as burned. For an ERC-20, tot…
- What Is Market Cap in Crypto? Circulating market cap = reference price × circulating supply The formula is simple; the inputs are not. A data provide…
- What Is Fully Diluted Valuation (FDV)? FDV = current reference price × provider-defined fully diluted supply CoinMarketCap currently defines FDV as price time…
- Tokenomics The term bundles **supply** (max, circulating, issuance, burns), **distribution** (teams, treasuries, unlocks, concentr…
- Governance tokens Governance tokens are units of **token-weighted voice**. Compound’s COMP is a documented example: delegate, propose abo…
- DAOs Vitalik Buterin was already trying to sort “DAO” from neighboring words in a May 2014 Ethereum Foundation post. The 201…
- NFTs **Fungible** tokens are interchangeable: one unit is as good as another. **Non-fungible** tokens are distinguishable. O…
- Stablecoins Stablecoins are tokens, not a single technical standard. Fiat-backed coins such as USDC and USDT depend on an issuer, r…
- What Are Wrapped Tokens? “Wrapped” covers at least two importantly different arrangements: Same-chain adapters. WETH represents ETH deposited in…
DeFi
Open financial protocols: exchanges, pools, lending, and the price-feed and liquidation mechanics they depend on.
- DeFi Decentralized finance is a loose label for lending markets, exchanges, stablecoin systems, derivatives, asset managers …
- Decentralized exchanges A DEX is a trading venue whose matching or pricing, and typically the custody of trading inventory, live in on-chain pr…
- Automated market makers In DeFi, an AMM is one **DEX architecture**, not the definition of a DEX (see Batch C). This article focuses on pool-ba…
- Liquidity pools Pools are shared reserves that a market-making rule can trade against. They are the inventory layer many DeFi AMMs use;…
- Slippage Market price, **price impact**, expected execution and actual execution are related but not identical. Impact is the di…
- What Is Impermanent Loss? Impermanent loss (IL) compares an LP position with a specific benchmark: holding the assets and quantities originally d…
- What Is Crypto Lending? Most major DeFi lending is pool-based and overcollateralized: suppliers provide liquidity, while borrowers pledge more …
- What Is Liquidation in DeFi? An initial loan-to-value limit controls new borrowing; a distinct liquidation threshold controls when an existing posit…
- Oracles Smart contracts cannot fetch arbitrary off-chain APIs without breaking deterministic consensus. Oracles source, verify …
- What Is a Flash Loan? A flash loan rents temporary liquidity plus transaction atomicity. The borrower contract can route the assets through e…
Advanced mechanics & infrastructure
Ordering and extraction, programmable accounts, rollups and data availability, bridges, Bitcoin payments, and storage.
- What Is MEV in Crypto? MEV was originally “miner extractable value.” “Maximal” is now broader: many chains do not use miners, and block constr…
- What Is a Sandwich Attack? A sandwich is an ordering-based form of MEV: an attacker places one transaction before a target and another after it. T…
- What Is Account Abstraction? An account is an onchain entity; a wallet is software or hardware used to control and interact with accounts. An Ethere…
- Layer 2 “Layer 2” is used loosely. On Ethereum, a careful meaning is an off-chain execution system that **derives security from…
- What Are Optimistic Rollups? Optimistic rollups move execution off Ethereum while using Ethereum for data availability, batch ordering and dispute s…
- What Are ZK Rollups? ZK rollups are more precisely called validity rollups: an L1 verifier accepts a state transition only with a valid proo…
- What Is Data Availability? Data availability (DA) is assurance that data required to verify or reconstruct a state transition was made available t…
- Bridges Blockchains do not natively share state. Bridges copy *meaning* across that gap: lock-and-mint, burn-and-mint, liquidit…
- What Is the Lightning Network? Lightning is a Bitcoin layer-2 payment-channel network. The BOLT specifications define cooperative off-chain transfers …
- What Is IPFS? IPFS stands for InterPlanetary File System and refers to open protocols, implementations and participating networks for…
Explore all topics
Every published article, in path order. Use search if you already know the term.
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- What is a blockchain?
- What is decentralization?
- What is cryptocurrency?
- What is Web3?
- What is a crypto wallet?
- Private key
- Seed phrase
- Bitcoin
- Ethereum
- Solana
- Smart contracts
- Gas fees
- What Is a Blockchain Node?
- What Is a Mempool?
- What Is a Nonce in Crypto?
- What Are Block Confirmations?
- What Is Finality?
- What Is a Blockchain Fork?
- Proof of work
- What Is Bitcoin Mining?
- What Is a Bitcoin Halving?
- Proof of stake
- Validators
- Staking
- Account Model vs UTXO
- What Is the EVM?
- What Is an ERC-20 Token?
- What Are SPL Tokens?
- What Is a Block Explorer?
- Self-custody
- Hot Wallet vs Cold Wallet
- What Is a Hardware Wallet?
- What Are Token Approvals?
- What Is Address Poisoning?
- What Is Multisig?
- CEX vs DEX
- Circulating vs Total vs Max Supply
- What Is Market Cap in Crypto?
- What Is Fully Diluted Valuation (FDV)?
- Tokenomics
- Governance tokens
- DAOs
- NFTs
- Stablecoins
- What Are Wrapped Tokens?
- DeFi
- Decentralized exchanges
- Automated market makers
- Liquidity pools
- Slippage
- What Is Impermanent Loss?
- What Is Crypto Lending?
- What Is Liquidation in DeFi?
- Oracles
- What Is a Flash Loan?
- What Is MEV in Crypto?
- What Is a Sandwich Attack?
- What Is Account Abstraction?
- Layer 2
- What Are Optimistic Rollups?
- What Are ZK Rollups?
- What Is Data Availability?
- Bridges
- What Is the Lightning Network?
- What Is IPFS?