Genesis block
First block of the Bitcoin system created by Satoshi Nakamoto on January 3, 2009.
The Genesis Block is the first block of the Bitcoin system. It signifies the concrete launch of Bitcoin. The Genesis Block was created by Bitcoin's anonymous founder, Satoshi Nakamoto, on January 3, 2009. Its hash is:
000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f
This block contains only a coinbase transaction that generates 50 bitcoins as a reward for the miner (in this case, Satoshi Nakamoto himself). This block includes a message embedded in the coinbase transaction:
The Times 03/Jan/2009 Chancellor on brink of second bailout for banks
This quote is a reference to an article from The Times newspaper. The message is interpreted as a critique of the traditional financial system and its excesses, which partly motivated the creation of Bitcoin as a monetary alternative.
Since it embodies the very first block of the Bitcoin blockchain, the Genesis Block obviously does not have a field containing the hash of the previous block (because there isn't one). Moreover, the 50 bitcoins generated as a reward in this block are not spendable at the protocol level.
TermDefinition
51% attack
An attack where a malicious actor controls more than half of the mining hash power, allowing them to manipulate transactions, notably by performing double spends.
Account
In an HD wallet, a derivation level (depth 3) allowing hierarchical organization of keys and addresses.
Activation method
The process by which the Bitcoin community decides to activate a soft fork, seeking consensus among miners and users to avoid a blockchain split.
Adaptor signature
A cryptographic technique linking a signature to a secret, such that publishing the signature reveals the secret. Useful for atomic swaps without a trusted intermediary.
Addr
An old Bitcoin network message that allowed communicating IP addresses of nodes accepting connections. Replaced by addrv2 (BIP155) to support longer address formats.
Addr.dat
An old file in Bitcoin Core that stored information about network peers. Replaced by peers.dat since version 0.7.0.
Address reuse
A discouraged practice of using the same Bitcoin address multiple times to receive payments, which harms privacy by allowing funds to be traced.
Address spoofing
An attack where a malicious actor creates an address closely resembling the victim's to deceive them and divert their payments.
Addrv2
A new network message format (BIP155) allowing the broadcasting of Bitcoin node addresses. Supports longer addresses such as Tor v3 or I2P.
Agorism
A libertarian political philosophy advocating economic action outside of state control (counter-economy) to progressively undermine state power.
Air cooling
A cooling system for mining machines using fans to dissipate heat. The most widespread and least expensive method.
Altcoin
Designates any cryptocurrency other than Bitcoin. A contraction of alternative and coin.
Aluvm
A virtual machine designed for deterministic execution of smart contracts, notably within the context of the RGB protocol on Bitcoin.
Analysis heuristic
An empirical method used to trace Bitcoin flows on the blockchain based on observable characteristics within transactions.
Ancestor mining
A principle whereby a miner selects transactions taking into account the fees of parent transactions, not only their own fees. Also called CPFP.
Anchor
In the RGB protocol, a set of data proving the inclusion of a commitment in a Bitcoin transaction, without publicly revealing its content.
Anchor outputs
A mechanism on Lightning allowing adjustment of the fees of a commitment transaction after its creation, to ensure quick channel closure.
Anchors.dat
A Bitcoin Core file storing IP addresses of nodes the client was connected to before shutdown, to facilitate reconnection on restart.
Anonsets (anonymity sets)
Indicators measuring the degree of privacy of a UTXO by counting the number of indistinguishable UTXOs in a set, typically after a coinjoin.
Anyprevout (apo)
A proposal (BIP118) adding new SigHash flags allowing the creation of signatures that do not cover any specific input of the transaction.
51% attack
An attack where a malicious actor controls more than half of the mining hash power, allowing them to manipulate transactions, notably by performing double spends.
Account
In an HD wallet, a derivation level (depth 3) allowing hierarchical organization of keys and addresses.
Activation method
The process by which the Bitcoin community decides to activate a soft fork, seeking consensus among miners and users to avoid a blockchain split.
Adaptor signature
A cryptographic technique linking a signature to a secret, such that publishing the signature reveals the secret. Useful for atomic swaps without a trusted intermediary.
Addr
An old Bitcoin network message that allowed communicating IP addresses of nodes accepting connections. Replaced by addrv2 (BIP155) to support longer address formats.
Addr.dat
An old file in Bitcoin Core that stored information about network peers. Replaced by peers.dat since version 0.7.0.
Address reuse
A discouraged practice of using the same Bitcoin address multiple times to receive payments, which harms privacy by allowing funds to be traced.
Address spoofing
An attack where a malicious actor creates an address closely resembling the victim's to deceive them and divert their payments.
Addrv2
A new network message format (BIP155) allowing the broadcasting of Bitcoin node addresses. Supports longer addresses such as Tor v3 or I2P.
Agorism
A libertarian political philosophy advocating economic action outside of state control (counter-economy) to progressively undermine state power.
Air cooling
A cooling system for mining machines using fans to dissipate heat. The most widespread and least expensive method.
Altcoin
Designates any cryptocurrency other than Bitcoin. A contraction of alternative and coin.
Aluvm
A virtual machine designed for deterministic execution of smart contracts, notably within the context of the RGB protocol on Bitcoin.
Analysis heuristic
An empirical method used to trace Bitcoin flows on the blockchain based on observable characteristics within transactions.
Ancestor mining
A principle whereby a miner selects transactions taking into account the fees of parent transactions, not only their own fees. Also called CPFP.
Anchor
In the RGB protocol, a set of data proving the inclusion of a commitment in a Bitcoin transaction, without publicly revealing its content.
Anchor outputs
A mechanism on Lightning allowing adjustment of the fees of a commitment transaction after its creation, to ensure quick channel closure.
Anchors.dat
A Bitcoin Core file storing IP addresses of nodes the client was connected to before shutdown, to facilitate reconnection on restart.
Anonsets (anonymity sets)
Indicators measuring the degree of privacy of a UTXO by counting the number of indistinguishable UTXOs in a set, typically after a coinjoin.
Anyprevout (apo)
A proposal (BIP118) adding new SigHash flags allowing the creation of signatures that do not cover any specific input of the transaction.