Cross-Chain

Cross-chain describes any activity that moves value or information between two separate blockchains, which by default cannot see each other at all. Because a Bitcoin node has no knowledge of Ethereum state, cross-chain transfers rely on an intermediary: a bridge that locks tokens on one side and issues a representation on the other, a messaging protocol that relays proofs, or a swap that pairs two transactions atomically. Each of these adds trust assumptions and code that has repeatedly proved to be a weak point in crypto security. Practical habits matter — confirm you are sending on the network the recipient expects, verify the token contract you receive, and treat wrapped assets as claims on a bridge rather than as the original coin.