Finality
Please note, the values on the page reflect the time required to achieve ordering finality, at which point transactions cannot be reverted or reordered. For simplicity, they do not include the overhead time to reach L1 finality, which is the same for all projects. The actionable settlement time on the L1 (that affects your ability to withdraw your funds on the L1) for these transactions may be longer. In most other cases, however, this does not apply (e.g., when transferring funds to an exchange). For more information on how finality works for L2 transactions, check our article.
Rollups are L2s that periodically post state commitments to Ethereum. These commitments are validated by either Validity Proofs or are accepted optimistically and can be challenged via Fraud Proof mechanism within a certain fraud proof window. Additionally L2 data is also posted to Ethereum, hence there are no additional trust assumptions introduced.
