Encyclopedia

This Archive aims to provide the glossary terms and docs you need to understand Bitcoin and start building Bitcoin-based applications.

H

Hard fork

A permanent divergence in the block chain, commonly occurs when non-upgraded nodes can’t validate blocks...

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Hardened extended key

A variation on HD wallet extended keys where only the hardened extended private key can...

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HD protocol

The Hierarchical Deterministic (HD) key creation and transfer protocol (BIP32), which allows creating child keys...

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HD wallet

The Hierarchical Deterministic (HD) key creation and transfer protocol (BIP32), which allows creating child keys...

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HD wallet seed

A potentially-short value used as a seed to generate the master private key and master...

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Header

An 80-byte header belonging to a single block which is hashed repeatedly to create proof...

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Header chain

A chain of block headers with each header linking to the header that preceded it;...

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Headers-first sync

Synchronizing the block chain by downloading block headers before downloading the full blocks.Not to be...

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Height

The number of blocks preceding a particular block on a block chain. For example, the...

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High-priority transaction

Transactions that don’t have to pay a transaction fee because their inputs have been idle...

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Documentation