Decode finance jargon with Kite

A second proof beyond your password, ideally an authenticator app or a hardware key. SMS codes are the weakest form, because phone numbers can be taken over.

Wallets that behave like normal apps. Spending limits, someone else covering the network fee, recovery without a phrase. The crypto machinery is still there, it is just no longer your problem.

The United States' batch transfer system, carrying salaries, bills and most payments that are not on a card. Cheap, slow by design, and reversible in a way card and blockchain payments are not.

The merchant's side of a card payment. The acquirer signs the shop up, takes the payment in, and pays the shop out, keeping a cut on the way through.

An attacker sends you a dust transaction from an address that looks like one you use, hoping you copy it out of your history next time. Always check the whole address, not the first and last four characters.

China's largest payment app and the QR code most Chinese merchants display. Foreign visitors can link some overseas cards, though acceptance and limits vary by card type.

Any cryptocurrency that is not bitcoin. The word stretches from major networks to a token created that morning, which is precisely why it tells you nothing about quality.

The formula that prices a decentralised exchange's pool. No order book and no human quoting, just a curve that moves as the pool's balance changes.

What a card costs you to keep, as opposed to what it costs you to use. It is the first number worth checking, because it is charged whether you spend anything or not.

Permission you grant a smart contract to spend tokens from your wallet, often with no limit and no expiry. Old approvals from apps you have forgotten are a standing risk worth revoking.

The annualised return including compounding. In crypto it is often quoted on rewards paid in a volatile token, so a large number can shrink as you earn it.

Taking cash out of a machine with your card. On crypto cards it is usually the most expensive thing you can do, and it often arrives later than the card itself.

The instant yes or no when you tap. The amount is held rather than taken, which is why a hotel or a petrol station can reserve more than you eventually pay.

A setting that turns one asset into another by itself, usually a volatile token into a stablecoin, either the moment it arrives or the moment you spend.

What you can spend right now. In a stablecoin app this is the tokens sitting in your wallet, shown to you as a dollar figure rather than as a token count.

A Layer 2 network built on top of Ethereum, designed so a transfer costs cents rather than dollars while still settling down to Ethereum underneath.

The first six to eight digits of a card number. They tell a merchant which bank issued the card, in which country, and of what type, which is how some sites refuse certain cards before you have finished checking out.

Your face or fingerprint used to unlock an app or approve a payment. It stays on the device: what travels is a yes, not your fingerprint.

A batch of transactions confirmed together and chained to the one before it, which is what makes rewriting history impractical.

A public search engine for a blockchain. Look up any address or transaction and see its status, amount and history without an account or a login.