Atomic Swaps and HTLCs
13 min readarticleIncludes quiz · 1 questions
Imagine swapping a $20 bill for euros with a stranger, but with a guarantee that either both of you get what you want or neither of you loses anything. That is an atomic swap — trustless exchange enforced by cryptography.
Understand the cryptographic magic that makes Lightning payments atomic and trustless.
Hash Time-Locked Contracts (HTLCs):
- •Hash Lock: Payment requires a secret preimage
- •Time Lock: Refund after timeout
- •Atomic: All-or-nothing execution
- •Trustless: No intermediary can steal funds
HTLCs enable multi-hop payments where either everyone gets paid or no one does.
Key Takeaway
Atomic swaps use the same hash time-locked contracts (HTLCs) that power Lightning routing. They enable cross-chain trading without trusting an exchange or a counterparty.
Test Your Knowledge
1 questions · Passing score: 80%
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