KoinlyticsBitcoin's block size and 10-minute cadence mean the base layer can handle around 7 transactions per second globally. Not enough for coffee. Lightning is Bitcoin's scaling answer: move payments off-chain into private channels, settle to chain only when a channel opens or closes.
A payment channel in one paragraph
Alice and Bob each fund a 2-of-2 multisig address. Now they can rebalance the split between them off-chain by exchanging signed but unbroadcast transactions. Any pending state can be broadcast at any time by either party to close the channel. Only the opening tx and the final closing tx hit chain.
HTLCs let you pay strangers
Alice does not need a direct channel with Bob to pay Bob. If Alice has a channel with Carol, and Carol has one with Bob, Alice can route through Carol. Hashed Time-Locked Contracts (HTLCs) make this safe: Bob generates a secret, hashes it, and only reveals the secret when Carol pays him. Alice's payment to Carol is only valid if Carol reveals the same secret. Either the whole chain settles or nothing does.
What it feels like in practice
- Coffee-sized payment: under a satoshi in fees, settles in half a second.
- Global remittance to a Lightning wallet: seconds, not days.
- Streaming: Podcasting 2.0 apps stream sats per second while you listen.
The catch you should know
Liquidity has to exist in the direction you want to pay. If you have a well-funded channel with your exchange but that exchange has no capacity to route to your friend, your payment fails. Wallets like Phoenix and Breez auto-manage this for you but you pay for the abstraction with slightly higher setup fees. Custodial Lightning (Wallet of Satoshi, Cash App) removes the friction entirely but you are trusting a third party again.
Where Lightning fits
Lightning is not competing with Solana or Visa for TPS. It is optimizing for the specific case where the payment endpoints trust the network of Bitcoin and want to settle in bitcoin. That is a smaller market than "all payments" but a bigger one than most crypto people think, and it grows every time an exchange in a country under capital controls integrates it.