UTXO and account models, consensus, confirmations, forks, finality, and layers.
By the end, you should be able to
- Compare UTXO and account-based state models.
- Explain why confirmation and finality depend on network design.
- Distinguish base layers, scaling layers, and bridges.
The same payment, different records
Illustrative state models explain why tools and fees vary by network.
Two ways to represent state
Bitcoin uses unspent transaction outputs (UTXOs): transactions consume previous outputs and create new ones. Account-based networks maintain balances and other state at accounts. Both models can transfer value, but they differ in transaction construction, privacy patterns, fee estimation, and application design.
Agreement, confirmations, and finality
Consensus rules determine which blocks a network accepts and how participants agree on the canonical history. Confirmations increase confidence after inclusion, while finality describes the network’s guarantee that a block will not be reverted under its stated assumptions. The meaning and timing differ across proof-of-work, proof-of-stake, and other designs.
Networks and layers have different trust assumptions
A base layer provides settlement and consensus for its own state. A scaling layer may execute transactions elsewhere and publish data or proofs to a base layer. A bridge or messaging system adds another verification, custody, or signer dependency; it does not make two networks one shared ledger.
What this does not tell you
- UTXO and account models have many protocol-specific variations.
- A confirmation is not a universal measure of finality or settlement risk.
- Layer-2 and bridge security depends on its contracts, operators, proofs, data availability, and exit process.
Compare two network designs
Use public documentation to compare how two networks record and settle a transfer.
- Choose Bitcoin and one account-based network.
- Record the state model, fee resource, block/confirmation convention, and finality assumption for each.
- List one fact the explorer shows and one trust assumption the explorer cannot prove.
Check your understanding
1. What does a UTXO represent?
2. What do confirmations generally indicate?
3. What does a bridge add?