The EVM

The Ethereum Virtual Machine, or EVM, is the execution environment that runs smart contracts. It turns high-level code into a deterministic sequence of tiny operations every Ethereum node can reproduce.

You can think of bytecode as the contract's machine language. The EVM steps through those instructions, tracks gas usage, reads calldata, and decides whether execution finishes successfully or reverts everything.

This design makes Ethereum programmable without letting contracts run arbitrary server code. The sandbox is intentionally narrow, which helps the network stay consistent even when millions of users and many different apps depend on it.