evM

The Ethereum Virtual Machine (EVM) is the runtime environment for smart contracts on the Ethereum blockchain. It is a stack-based, Turing-complete virtual machine that executes bytecode compiled from high-level languages such as Solidity and Vyper. The EVM is designed to be deterministic and sandboxed, so all full nodes can reproduce contract execution and outcomes.

The EVM operates on 256-bit words, using a stack, memory, and persistent storage. Transactions that call or deploy contracts are translated into a sequence of EVM instructions executed by every node. Execution proceeds instruction by instruction, with gas used to pay for computational steps; if gas runs out, execution halts and any state changes are reverted.

Gas is a separate unit of account paid in Ether. Each opcode has a predefined gas cost, and more complex operations or storage access cost more gas. This mechanism limits resource usage and provides incentives for efficiency, while preventing infinite loops and certain attacks.

Contracts are deployed as EVM bytecode produced by compilers such as Solidity and Vyper. The EVM runs on Ethereum client implementations like Geth, Besu, OpenEthereum, and other compatible clients, ensuring network consensus. Its design has guided protocol upgrades through hard forks that adjust gas costs, opcode behavior, and security, while preserving compatibility with existing bytecode.