# Important Concepts

- [High Level](/important-concepts/high-level.md)
- [Web3](/important-concepts/high-level/web3-the-semantic-web-of-value.md)
- [Timestamping](/important-concepts/high-level/time-stamping-and-on-chain-data.md)
- [SPV](/important-concepts/high-level/simplified-payment-verification-spv.md)
- [UTXO vs Account Based](/important-concepts/high-level/utxo-base-vs-account-based-systems.md): Two methods of tracking ownership and transaction history
- [Linked Keys](/important-concepts/high-level/linked-keys-42.md)
- [Smart Contracts](/important-concepts/high-level/smart-contracts.md)
- [Details](/important-concepts/details.md)
- [Hash Functions](/important-concepts/details/cryptographic-hash-functions.md)
- [Merkle Trees](/important-concepts/details/merkle-trees.md)
- [Sighash Flags](/important-concepts/details/sighash-flags.md)
- [Script](/important-concepts/details/script.md)
- [SPV](/important-concepts/details/spv.md)
- [Deep Dive](/important-concepts/details/spv/deep-dive.md): Some low level explainers and examples to improve understanding.
- [Payments Flow](/important-concepts/details/spv/payments-flow.md): Paymail Capability Extensions
- [Data Models](/important-concepts/details/spv/data-models.md): What data is sent between counterparties for SPV Payments?
- [Broadcasting](/important-concepts/details/spv/broadcasting.md): Transaction Broadcasting from SPV Wallet