Crypto & DeFi

Non-Custodial Wallet Risks Covers the specific failure modes and security risks unique to crypto wallets where no third party holds the keys.

Non-Fungible Token Unique on-chain ownership records that distinguish digital assets from interchangeable coins and tokens.

Nothing-at-Stake Problem In naive proof-of-stake systems, validators can vote on all competing chain forks simultaneously at zero cost, undermining consensus security.

On-Chain vs Off-Chain Transactions Understand the difference between on-chain vs off-chain transactions and how Layer 2 networks and payment channels reduce costs while maintaining security.

OP Stack and the Superchain Explained Learn how the OP Stack is a modular codebase for building Optimism-compatible Layer 2 chains and how the Superchain vision aims to unify them.

Optimism Optimism is an Ethereum layer-2 rollup using optimistic rollup technology. It bundles transactions and posts them to Ethereum in compressed form, reducing costs and increasing throughput while inheriting Ethereum's security.

Optimistic Rollup A layer-2 scaling solution that assumes transactions are valid unless proven otherwise through a fraud-proof mechanism.

Optimistic Rollup vs ZK-Rollup Optimistic rollups use fraud proofs and a challenge period; ZK-rollups use validity proofs and settle faster. Each trades cost, speed, and verification complexity differently.

Options (Cryptocurrency) Derivatives granting the right to buy or sell a cryptocurrency at a predetermined price and time.

Order Book Depth in Crypto Markets Learn how to read order book depth charts, assess liquidity risk with bid-ask spreads, and understand why depth varies across crypto exchanges.

Order Book DEX vs AMM How order book DEXs and automated market makers differ in execution model, price discovery, and capital efficiency, and which suits different trading needs.

Orphaned Blocks and Reorgs Chain reorganization when a longer block sequence supersedes shorter one; transaction finality implications.

Overcollateralized Lending DeFi lending mechanism where borrowers must deposit collateral worth more than the loan, protecting the protocol against price volatility.

Paying a Large Crypto Tax Bill in Installments IRS installment agreement options for crypto capital-gains tax bills: eligibility, interest rates, penalties, and when long-term payment terms make sense.

Permissioned Blockchain A permissioned blockchain restricts who can participate in the network. Only approved nodes can validate transactions and join, contrasting with permissionless blockchains where anyone can participate.

Perpetual Futures Funding Rate Explained How perpetual futures funding rates anchor derivative prices to spot, who pays whom, and how traders use funding as a sentiment indicator.

Perpetual Protocol (DeFi) Decentralized futures contracts with no expiry date, settled via automatic funding rates in AMM or order-book environments.

Plasma Exit Mechanism Protocol allowing users to withdraw funds from plasma sidechain to the blockchain root chain, including fraud-proof safeguards.

Points vs Tokens in DeFi: What Is the Difference Understand the difference between points and tokens in DeFi: off-chain loyalty programs versus on-chain assets, and their regulatory, technical, and financial implications.

Polkadot Polkadot is a multi-chain blockchain network that connects parallel chains (parachains) through a shared security model. It enables interoperability between different blockchains and uses proof-of-stake consensus.

Polkadot Parachains Explained Understand Polkadot parachains: how they lease slots on the relay chain and enable cross-chain interoperability in a multi-chain network.

Polkadot XCM Cross-Chain Messaging XCM is Polkadot's message format for cross-chain asset transfers and program execution. Explains how parachains and external chains interoperate.

Polygon Polygon is a framework for building Ethereum-compatible blockchains and scaling solutions. It provides multiple scaling options, from sidechains to rollups, allowing developers to customise security and performance trade-offs.

Polygon PoS vs Polygon zkEVM Compare Polygon PoS sidechain and Polygon zkEVM rollup: security models, finality times, and compatibility trade-offs explained.

Practical Byzantine Fault Tolerance Castro and Liskov's 1999 state-machine replication protocol that achieves consensus finality in permissioned and proof-of-stake networks.

Preconfirmations in Rollup Transactions How preconfirmation mechanisms on rollup transactions provide near-instant soft finality before formal batch inclusion, and how they differ from true settlement.

Privacy Coin Cryptocurrencies using cryptographic protocols to obscure sender identity, receiver identity, and transaction amounts.

Private Blockchain A private blockchain is a restricted network where participation and validation are controlled by approved entities. Transactions may or may not be visible to the public, and governance is centralised.

Proof Aggregation A technique for combining hundreds of transaction-level zero-knowledge proofs into a single proof, amortising verification costs across many transactions.

Proof of Burn Consensus Explained How proof of burn consensus explains mining rights from coin destruction, and compares economic trade-offs to proof of work and proof of stake.

Proof of History Solana's verifiable delay function that embeds a cryptographic clock into the ledger to order events and reduce consensus overhead.

Proof of Publication in Blockchain Scaling Proof of publication blockchain data availability guarantees rollups can post transactions and recover state. Learn why broadcast ≠ storage.

Proof of Reserves How cryptocurrency exchanges cryptographically verify they hold sufficient customer assets without exposing sensitive account data.

Proof of Solvency vs Proof of Reserves in Crypto Proof of reserves shows assets exist; proof of solvency proves assets exceed liabilities. Why the distinction matters for exchange security audits.

Proof of Space-Time Chia's consensus mechanism using unused disk space and elapsed time instead of energy-intensive computation.

Proof of Stake Variants Different mechanisms for securing blockchains through staking, including liquid staking, solo staking, and pool staking.

Proof of Work vs Proof of Stake Proof of work vs proof of stake: how energy use, security model, and validator economics differ between blockchain consensus mechanisms.

Proof-of-Authority Proof-of-authority is a consensus mechanism where a set of approved validators validate transactions. Validators stake their reputation rather than cryptocurrency. It is used in permissioned blockchains and testnets.

Proof-of-Stake Proof-of-stake is a consensus mechanism where validators lock up collateral (cryptocurrency) to earn the right to propose blocks. Validators who misbehave lose their collateral (are slashed), making attacks economically irrational.

Proof-of-Work Proof-of-work is a consensus mechanism where nodes (miners) compete to solve difficult mathematical puzzles. The first to solve a puzzle gets to propose the next block and receives a reward, securing the network through energy expenditure.

Proposer-Builder Separation Explained Proposer-builder separation decouples block building and validation in proof-of-stake networks to reduce MEV extraction and improve fairness.

Proto-Danksharding EIP-4844, Ethereum's 2024 upgrade introducing blob-carrying transactions as the interim step toward full Danksharding data scaling.

Protocol-Owned Liquidity How DeFi protocols accumulate and manage their own liquidity reserves instead of relying on external LPs to provide capital.

Proving Cost in ZK Rollups How proving cost in ZK rollups—hardware and compute expenses for validity proofs—affects user fees and economic sustainability.

Public Blockchain A public blockchain is a decentralised network where anyone can participate as a node or validator without permission. All transactions are visible to the public, and the network is not controlled by any single entity.

Qualified Custodian Rule for Crypto The regulatory standard that determines which entities may safely hold client cryptocurrencies under US investment adviser rules.

Range Orders in Concentrated Liquidity Pools How range orders in concentrated liquidity work by placing capital in a narrow price range, effectively mimicking a limit order.

Real Yield DeFi vs Inflationary Yield Real yield comes from actual fee revenue; inflationary yield from new tokens. See which protocols are sustainable and which are wealth transfers.

Real-World Asset Tokenization Digital tokens representing ownership or claims on physical assets like treasuries, real estate, and commodities.

Real-World Asset Tokenization in DeFi How real-world assets like treasuries and invoices are tokenized for DeFi protocols, unlocking yield but introducing custody and oracle risks.

Rebase Token vs Stablecoin Compare elastic-supply rebase tokens that adjust wallet balances algorithmically with stablecoins that peg via reserve or collateral backing.

Rebasing Token Tokens that algorithmically adjust supply and every holder's balance to maintain a target price peg through periodic positive or negative rebases.

Receipt Token Protocol-issued tokens representing a claim on deposited collateral, redeemable for the underlying asset plus accrued yield, commonly used in lending and yield protocols.

Recursive SNARK A cryptographic proof that verifies other proofs, enabling nested computation compression and exponential scaling of proof batching.

Rehypothecation Risk in DeFi Rehypothecation risk in DeFi occurs when collateral is reused across multiple protocols simultaneously, amplifying systemic risk during market stress.

Restaking Restaking is a mechanism where cryptocurrency already staked in a proof-of-stake network is used to secure additional applications or sidechains. It increases yield but introduces additional slashing risks.

Revenue-Sharing Token Revenue-sharing tokens entitle holders to a portion of protocol fees or profits. Learn how distributions work on-chain and regulatory considerations for token holders.

Ripple XRP Ripple is a real-time payment settlement network and currency exchange system. XRP is its native cryptocurrency used to pay for transactions and bridge different currencies on the Ripple Ledger.

Rollup Cost Breakdown Per Transaction A rollup transaction fee splits across L2 execution, data posting, and proof costs—each scales differently as network throughput rises.

Rollup Escape Hatch Mechanism How a rollup escape hatch enables forced exits and direct L1 withdrawals when a rollup operator goes offline or censors transactions.