# Introducing zkSync Era
**zkSync** is a [ZK rollup](https://era.zksync.io/docs/dev/fundamentals/rollups.html#what-are-zk-rollups), a trustless protocol that uses cryptographic validity proofs to provide scalable and low-cost transactions on Ethereum. In zkSync, computation is performed off-chain and most data is stored off-chain as well. As all transactions are proven on the Ethereum mainchain, users enjoy the same security level as in Ethereum.
zkSync Era is made to look and feel like Ethereum, but with lower fees. Just like on Ethereum, smart contracts are written in Solidity/Vyper and can be called using the same clients as the other EVM-compatible chains.
You don't need to register a separate private key before usage; zkSync supports existing Ethereum wallets out of the box. At this time, zkSync is solely run and operated by the zkSync team's servers and is therefore centralized. However, this will be transitioned to a decentralized system shortly.
Find more about zkSync era:
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