Blockchain Technology Study Guide 2026

A VRF generates randomness that is unpredictable in advance but publicly verifiable afterward, used for secret committee selection.

A blockchain is fundamentally a decentralized, distributed ledger technology that operates on a peer-to-peer network. It consists of a continuously growing list of records, called blocks, which are cryptographically linked together. This structure ensures transparency, immutability, and resistance to censorship, allowing participants to maintain and validate transactions without a central authority.

Indexed event params are stored as topics, letting clients efficiently filter logs by their values.

Isolating signing keys in an HSM or remote signer keeps them off the internet-facing node and limits exposure.

Reentrancy occurs when an external call is made before state changes, letting the callee re-enter and exploit stale state.

Caps, multisig, and transparency create accountability and limit unilateral spending.