Bitcoin Stack Exchange is a question and answer site for Bitcoin crypto-currency enthusiasts. It only takes a minute to sign up.
Sign up to join this community
Anybody can ask a question
Anybody can answer
The best answers are voted up and rise to the top
Hello can you please explain what “TXes” are and What “Block Headers & Targets” and “Headers Below Target” mean. Thank you very mcuch.
- TX: Transaction.
- Transaction: Most Bitcoin transactions probably represent one person or organisation paying one other but some transactions represent an exchange paying hundreds of customers or a mixing transaction that represents hundreds of smaller transactions that are not represented individually. There are more exotic forms of transactions, and probably more types being developed.
- Block Header: Information other than transaction details.
E.g. hash of prior transaction, date & time, …
- Target: A target number for miners, their blocks must have a hash less than the current target. every node calculates the target in a standard way. The target moves up and down to try to keep the network’s mining rate to 1 block every 10 minutes.
- Headers below Target: Headers of blocks whose hash is less than the current target.
- Hash: A large number. One that is mathematically derived from a much larger set of data. The mathematics ensures that the hash looks essentially random but is always the same for the same set of data but the hash is completely different if even one bit of the data is different. You can’t recreate the data from the hash but you can use the hash to check the data hasn’t been altered.
- Block: A list of Bitcoin transactions together with a block-header.
- Wallet: A software (or firmware) program that securely holds one or more private-keys. Wallets don’t contain money. This unintuitive aspect has often been used by conmen to steal money from people new to Bitcoin.
- Password: A relatively short sequence of letters, digits and punctuation that is used to protect the secret contents of a wallet. Changing the password does not make a wallet safe to use if someone else has previously had access to it.
- Node: A program that uses the Bitcoin network protocols. Typically a wallet.
- Full Node: A Node that keeps its own copy of the blockchain and therefore doesn’t need to trust nodes run by potentially malicious strangers.
- Pruned Node: A Full-Node that discards some information from the blockchain once it no longer needs it. This keeps down usage of disk space but makes the Bitcoin network less resilient.
- Private Key: A large number. One that is kept secret. One that can be used to make digital signatures. Knowing a private key allows you to spend money, regardless of what wallets contain that private key. This aspect is often used by conmen to steal money from people new to Bitcoin.
- Public Key: A large number. One that is made public. One that has a special mathematical relationship to a Private Key. One that can be used to check that a signature is genuine without knowing the private key. Because mathematics.
- Digital Signature: A large number. One that can be produced by a mathematical operation involving a private key and the data that is considered signed. Although a signature can be produced from a private-key, mathematics prevents the private-key being produced from the signature.
- Address: A large number. One that represents and is mathematically derived from a Bitcoin-script used in a transaction. This address does not identify a place person or organisation. An address can generally not be used to find someone you sent money to. Don’t think of this as a “wallet address” (no such thing really), that’s just sloppy thinking that will confuse you.
- Blockchain: A linked list of blocks. Linked by block hashes. The Bitcoin blockchain represents a transaction journal that has the details of every Bitcoin transaction since the beginning of time. Every Bitcoin wallet program either has its own copy or access to a copy that it trusts.
- Account: There are no accounts in the Bitcoin network protocols or blockchain. Bitcoin doesn’t need accounts. Bitcoin doesn’t keep track of who owns money or how much.
- Validation: Not the same as Confirmation – don’t get these muddled up. Every Node validates transactions and blocks. This means it checks all the Consensus Rules. E.g.that block-hashes are below target.
- Confirmation: Not the same as Validation – don’t get these muddled up. A Confirmation of a transaction is one block that either contains that transaction or which builds on top of such a block (is linked to it by a chain of prior-block hashes).
- Consensus rules: A set of rules that all Bitcoin nodes agree to and individually apply. These rules define Bitcoin. A change in the rules can potentially split Bitcoin into two different currencies. Note that consensus is mostly an emergent phenomenon, not one that is explicitly or directly managed or controlled.
One source of help in understanding Bitcoin terms is the search facility in one Bitcoin Wiki. For example see its entry for address