Lightning Network

A second-layer Bitcoin payment network that enables instant, low-fee transactions.

The Lightning Network is a payment system built on top of Bitcoin. It moves transactions off the main blockchain into a network of payment channels, allowing instant, near-free transfers while inheriting Bitcoin's security guarantees.

The trick is that not every payment needs to be recorded on Bitcoin's main chain. Two parties open a channel with one on-chain transaction, exchange thousands of payments back and forth off-chain, and close the channel with one final on-chain transaction. The fee per off-chain payment is microscopic.

For users it just works. Scan a QR code, confirm the amount, sats arrive in roughly a second. The complexity is hidden in the wallet. Lightning is what makes Bitcoin practical for everyday spending — buying coffee, tipping a creator, sending allowance to a kid.

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Lightning Network

Send Bitcoin instantly with near-zero fees. Here is how it works and how your family can use it today.

Related terms

Glossary

Channel

A two-party Lightning payment connection. Open it once, exchange thousands of payments off-chain, close it when done.

Glossary

Invoice

A Lightning payment request — a string starting with "lnbc..." that encodes amount, description, and destination.

Glossary

Sats

Short for satoshis — the smallest unit of Bitcoin. 100 million sats = 1 BTC.

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