Blockchain fundamentals

UTXO selection

A Bitcoin transaction consumes prior outputs and creates new ones.

Reference note · Sources below

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Bitcoin: inputs and outputs — Diagram: Bitcoin: inputs and outputs · Open image ↗

In this article

Overview
Why it matters
What to check
Sources

Overview

A Bitcoin transaction consumes prior outputs and creates new ones.

Why it matters

Coin selection changes fees, privacy and change outputs.

What to check

Trace complete inputs and outputs instead of account-style assumptions.

Sources

Bitcoin developer documentation

Related reading

chains

Cardano: extended UTXO and application risk

Transaction structure helps explain execution, but cannot validate a project's promises.

foundations

A transaction's path from signature to confirmation

Signing, broadcasting, inclusion and finality are distinct events.

foundations

Bitcoin UTXOs: the outputs behind a wallet balance

Inputs consume earlier outputs; new outputs define who can spend the resulting amounts.

foundations

Bitcoin halvings: a programmed subsidy reduction

The schedule changes new issuance; it does not program a market return.