The Lightning Network is a Layer 2 payment protocol built on top of Bitcoin that enables near-instant, near-zero-fee Bitcoin transactions by routing payments through a network of off-chain payment channels. It addresses Bitcoin’s fundamental scalability limitation: Bitcoin’s 7 TPS throughput and 10-minute block times make it impractical for small, frequent payments. The Lightning Network solves this by allowing two parties to open a direct payment channel by locking Bitcoin in a multi-signature address on-chain, then transact between themselves (and route payments through other channels) unlimited times off-chain, settling the final balance to Bitcoin only when the channel is closed.
How Lightning payments work: sender and receiver don’t need a direct channel — payments route through a network of intermediary nodes, each charging a tiny fee (often sub-satoshi). Payment routes are found automatically. Lightning enables: Micropayments — sending fractions of a cent economically; Streaming payments — paying by the second for content or services; Point-of-sale payments — Bitcoin accepted as fast as a card payment. El Salvador’s Bitcoin legal tender adoption was built on Lightning. Lightning is also the foundation for new Bitcoin-native applications including the Nostr social protocol and various AI agent payment rails where machines pay machines instantly in Bitcoin. Limitations: requires channels to be funded, routing can fail for large payments, and channels can be forced closed.
Example: A tourist in El Salvador buys a $3 coffee using a Lightning-enabled Bitcoin wallet. The payment settles in under 1 second with a $0.0001 fee — faster and cheaper than a credit card transaction.
Learn more: Lightning Network — Official Site
