Layer 1

A base blockchain, such as Bitcoin, Ethereum or Solana, whose own network of computers orders transactions and secures the ledger.

• Thousands of independent nodes each keep the full record and enforce the same rules, so no single party can rewrite history.
• Security comes from its consensus method, proof of work or proof of stake, which makes attacking the chain cost more than it could gain.
• Throughput, security and decentralisation pull against each other: more capacity needs costlier hardware, so fewer people can run nodes.
• Bitcoin handles about 7 transactions per second and Ethereum's base layer about 15–20; Solana does thousands, with far heavier hardware.