# Data availability

## Definition

Data availability is the property that transaction or state data needed to verify blockchain or rollup behavior can be obtained by participants that need to reconstruct or validate state.

## What it means in practice

Rollups can differ in where transaction data is published and how users or validators can recover it if a sequencer or service becomes unavailable.

## How this concept appears in Terenval Wallet

Terenval uses supported L2 networks as they are implemented; their data-availability design is a property of the network, not of the wallet.

**Important:** Low fees alone do not describe the full security model of an L2; data availability and settlement design also matter.

**[Install Terenval Wallet](https://wallet.terenval.com/?lang=en)**

## Related terms

- [layer 2](https://wallet.terenval.com/glossary/layer-2/)
- [rollup](https://wallet.terenval.com/glossary/rollup/)
- [sequencer](https://wallet.terenval.com/glossary/sequencer/)
- [finality](https://wallet.terenval.com/glossary/finality/)
- [zero knowledge rollup](https://wallet.terenval.com/glossary/zero-knowledge-rollup/)
- [optimistic rollup](https://wallet.terenval.com/glossary/optimistic-rollup/)

## Related Terenval Answers

- [Ethereum Layer 2 Networks and Gas Fees](https://wallet.terenval.com/answers/ethereum-layer-2-networks-and-gas-fees/)
- [Can One Crypto Wallet Manage Multiple Blockchains?](https://wallet.terenval.com/answers/can-one-crypto-wallet-manage-multiple-blockchains/)
- [How Does a Multi-Chain Crypto Wallet Keep Networks Separate?](https://wallet.terenval.com/answers/how-multi-chain-wallets-keep-networks-separate/)

Official page: https://wallet.terenval.com/glossary/data-availability/