Hard Fork
A hard fork changes blockchain consensus rules in a way that older unupgraded nodes cannot fully validate as compatible with the new…
Glossary terms starting with H
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Hardware Security Key
A hardware security key is a physical authenticator that stores or uses cryptographic credentials to prove possession during login, transaction approval, or…
Hardware Token
A hardware token is a physical security device used to generate, store, or prove authentication credentials, one-time codes, cryptographic keys, or transaction…
Hardware Wallet
A hardware wallet is a dedicated device that protects private keys and signs transactions while keeping key material isolated from general-purpose computers.…
Hardware Wallet Interface (HWI)
Hardware Wallet Interface is Bitcoin Core-related software that provides a standardized way for applications to communicate with supported hardware wallets. Reliable use…
Hash
A hash is a fixed-length or bounded-size output produced by applying a hash function to input data. In blockchain systems, hashes identify…
Hash Digest
A hash digest is the output value produced by a hash function for a particular message or data object. It is often…
Hash Function
A hash function maps input data of arbitrary or variable length to a fixed-length or bounded output called a hash digest. Cryptographic…
Hash-Based Payment Matching
Hash-Based Payment Matching is a matching method that uses a blockchain transaction hash as a principal key for associating an on-chain transfer…
Hashed Timelock Contract (HTLC)
A hashed timelock contract is a conditional payment mechanism that releases funds when a recipient reveals a secret value matching a known…
Healthcare Crypto Payment
Healthcare Crypto Payment is a cryptocurrency payment for healthcare services, medical products, insurance-related obligations, or health-sector business transactions where accepted. Sensitive data,…
Hedera Token Service (HTS)
Hedera Token Service is a protocol-level framework for creating and managing fungible and non-fungible tokens directly through Hedera network services. Issuers configure…
Herstatt Risk
Herstatt risk is foreign-exchange settlement exposure where one party pays its currency but the counterparty fails before delivering the other currency. Herstatt…
Hexadecimal
Hexadecimal is a base-16 notation that represents binary data with the characters 0 through 9 and A through F. Each hexadecimal character…
Hierarchical Deterministic Payment Address
Hierarchical Deterministic Payment Address is a payment address generated from a hierarchical deterministic wallet structure using a defined derivation path. It is…
Hierarchical Deterministic Wallet (HD Wallet)
A hierarchical deterministic wallet derives a structured tree of keys and addresses from one root seed using defined derivation rules. For Hierarchical…
High-Risk Address
A high-risk address is a blockchain address associated with indicators suggesting elevated sanctions, fraud, theft, laundering, or illicit-finance exposure. A score for…
High-Risk Crypto Payment
A high-risk crypto payment is a transaction that exceeds defined risk thresholds or presents indicators requiring enhanced controls. The designation may result…
High-Risk Customer
High-Risk Customer is a measurable uncertainty or exposure that presents elevated exposure based on identity, ownership, geography, products, behavior, transactions, or other…
High-Risk Jurisdiction
A high-risk jurisdiction is a country or territory assessed as presenting elevated financial-crime, sanctions, corruption, conflict, regulatory, or operational exposure. High-Risk Jurisdiction…
High-Risk Merchant
High-Risk Merchant is a measurable uncertainty or exposure that operates in circumstances associated with elevated fraud, disputes, regulatory, sanctions, fulfillment, reputation, or…
High-Risk Transaction
High-Risk Transaction is a measurable uncertainty or exposure that has characteristics indicating elevated fraud, sanctions, laundering, security, settlement, or operational exposure requiring…
High-Value Confirmation Policy
High-Value Confirmation Policy is a rule requiring stronger confirmation, review, or finality conditions for crypto payments above a defined value or risk…
High-Value Payment
A high-value payment is a payment considered large under a scheme, institution, business, or risk policy. The threshold depends on currency and…