What is Atomic Swap?
An atomic swap is a peer-to-peer exchange of cryptocurrencies across two different blockchains without a trusted intermediary. It uses hash time-locked contracts (HTLCs) so that either both transfers happen or neither does, making the trade atomic.
Why Atomic Swap matters
Understanding Atomic Swap is part of building a solid mental model of how Bitcoin, blockchain and Web3 systems actually work. Concepts in the Concepts category sit at the foundation of the broader stack — get them right and the rest is far easier.
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Related terms
- Lightning Network — Bitcoin's payment-channel scaling layer.
- Smart Contract — Code on a blockchain that automatically enforces its rules.
More concepts terms
- Decentralization — Distributing control across many independent participants.
- Bridge — A protocol that moves assets or messages between chains.
- Byzantine Fault Tolerance (BFT) — A system that works even when some nodes lie or fail.
- Staking — Locking tokens to secure a network and earn rewards.
- Validator — A node that proposes and attests to blocks in PoS.
- Layer 1 (L1) — A base blockchain network with its own consensus.
- Layer 2 (L2) — A scaling network that settles to a Layer 1.
- Rollup — An L2 that posts transaction data to L1 for security.
Keep exploring
Continue with the full blockchain glossary — 136 terms in total — or read the developer blog and FAQ for deeper context.