Transaction
blockchain · technical
A record submitted to a blockchain to make a payment or another permitted change.
1.general
A transaction is a record that asks the network to make a change, such as paying another person. Your wallet prepares the record and usually signs it before sending it to the network. Nodes check its rules; broadcasting alone does not mean it has been included in a block.
2.models
In a UTXO system, a transaction consumes named outputs and creates new outputs. In an account system, it commonly changes balances, nonces, and contract storage. Nodes independently check the applicable consensus and local relay rules.
3.lifecycle
A relayed transaction may enter a node's mempool before a miner includes it in a block. Inclusion gives it one confirmation; later blocks increase the cost of reorganizing that history. Unconfirmed transactions can be dropped, conflicted, or replaced according to network policy.
See how to read the transaction visualizer, or watch incoming activity in TX::Watch.
Technical reference: Bitcoin developer guide to transactions.
Related terms
Mempool
→A node’s local collection of valid transactions waiting to be included in a block.
blockchain · node
Block
→A batch of valid transactions added to a blockchain, linked to the previous block by a cryptographic hash.
mining · blockchain · security
Confirmations
→How many blocks have been added starting with the block that includes a transaction.
security · blockchain
Transaction Fee
→The network cost of processing a transaction, separate from the amount sent to the recipient.
blockchain · technical · basics
Unspent Transaction Output (UTXO)
→A discrete spendable output on a UTXO blockchain, similar to a digital coin that must be spent whole.
technical · blockchain
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