Bitcoin (BTC)

Overview

Bitcoin (BTC) is the native Coin used by the Bitcoin network. The protocol records ownership through unspent transaction outputs rather than account balances. A wallet creates a transaction by selecting spendable outputs, assigning value to recipient outputs, returning any remainder through a change output, and signing the result.

Bitcoin uses proof-of-work mining to order transactions and extend the canonical chain. Miners receive newly issued BTC and transaction fees when they produce accepted blocks. The issuance schedule decreases through periodic halvings and approaches a protocol maximum of 21 million BTC, although the amount practically available to markets is lower because some coins are lost or inaccessible.

Transaction fees are generally evaluated by fee rate relative to Virtual Byte (vByte) size. During high Blockspace Demand, a low-fee transaction can remain pending. Wallets may use Replace-by-Fee (RBF) to publish a conflicting higher-fee version, which is why merchants should not treat a first-seen unconfirmed transaction as final.

Bitcoin settlement follows Probabilistic Finality. Each additional accepted block reduces the likelihood that the payment will be removed by a competing branch, but no universal confirmation count fits every transaction. A merchant’s finality policy should consider value, delivery reversibility, network conditions, and any detected conflict.

For payment operations, BTC must be bound to the Bitcoin network, destination address, amount, transaction identifier, and confirmation state. A syntactically valid address or visible transaction is not enough. Systems should verify the actual recipient output, avoid confusing change with payment, and retrieve current provider support before creating or crediting a transaction.