Glossary
Ethereum Virtual Machine (EVM)
The deterministic 256-bit virtual machine that executes Ethereum smart contracts, and the de facto standard runtime cloned by most Layer-2s and alt-L1s.
The EVM is a stack-based virtual machine that runs the bytecode of every Ethereum smart contract. Every node executes the same opcodes on the same inputs and arrives at the same state, which is what keeps the chain deterministic.
"EVM-compatible" has become a marketing term because so many chains (Arbitrum, Optimism, Polygon, Avalanche C-chain, BNB Chain) re-use the EVM bytecode. A contract compiled for Ethereum mainnet generally deploys unchanged on any of them.