Glossary

Account Abstraction

Account Abstraction enhances transaction authorizations by making them programmable, offering more flexibility than Externally Owned Accounts (EOAs). This innovation aims to enrich user experiences and broaden the scope of transaction authorizations, differing from EIP-4337.

EVM Equivalent

EVM Equivalent means that a given protocol supports every opcode of Ethereum’s EVM down to the bytecode. Thus, any EVM smart contract works with 100% assurance out of the box.

EVM Compatible

EVM Compatible means that a percentage of the opcodes of Ethereum’s EVM are supported; thus, a percentage of smart contracts work out of the box. ZKsync is optimized to be EVM source-code compatible (with a custom compiler), not EVM equivalent.

Paymaster

A Paymaster is an account on the ZKsync network that can cover transaction fees for users. It can pay these fees directly and allow users to reimburse the fees using various digital assets.

SNARK (Succinct Non-Interactive Argument of Knowledge)

SNARKs are a kind of zero-knowledge proof system that are short and quick to verify. SNARKs are characterized by their use of the KZG (Kate, Zaverucha, and Goldberg) commitment scheme which uses elliptic curve cryptography.

ZKsync VM

ZKsync VM is the name of the architecture that enables zero-knowledge proof generation for the execution trace of smart contracts originally written for EVM.

ZK Rollup

In zero-knowledge (ZK) rollups the batch of transactions is verified for correctness on the Ethereum network. After the verification passes, the verified batch is considered final like any other Ethereum transaction. This is achieved through the power of cryptographic validity proofs (commonly called zero-knowledge proofs). With any batch of off-chain transactions, the ZK rollup operator generates a proof of validity for this batch. Once the proof is generated, it is submitted to Ethereum to make the roll-up batch final. In ZKsync, this is done via a SNARK, succinct non-interactive argument of knowledge.