A block in Ethereum is a unit of data that records transactions, executed smart contracts, and other service information. Each new block is added to the blockchain sequentially, forming a single chain.

The block consists of a header, a list of transactions, data on executed smart contracts, and service fields. The header contains information about the previous block, the state hash, validator data, creation time, and gas limit.

After the transition to Proof-of-Stake, blocks are added by validators, who are randomly selected from among the staking participants. A validator forms a block, includes transactions in it, signs it, and transmits it to the network, where other nodes confirm it.

Ethereum blocks include not only transactions, but also data on the execution of smart contracts. They are created faster, have a dynamic gas limit instead of a fixed size, and are processed by validators (in Bitcoin, miners).

Ethereum does not have a fixed block size — it depends on the gas limit. On average, a block takes up 80–100 KB.

Ethereum uses a decentralized blockchain with support for smart contracts.

EVM is a virtual machine that runs all smart contracts on the Ethereum network. It interprets bytecode, provides execution isolation, and guarantees the same result on all nodes in the network.

Blocks in Ethereum are created approximately every 12 seconds. This time may vary slightly depending on network load and validator activity.

Validators in the Ethereum network form and confirm blocks. They are selected randomly from among those who have locked their ETH in staking. They receive a reward for honest work, and fines for breaking the rules.

A block hash is a unique cryptographic identifier generated from the block header. It allows you to link blocks into a single chain and ensures data protection from counterfeiting: any change inside a block will change its hash.