Binance (2019)

A hardware wallet is a small device that keeps your private keys offline and signs transactions inside itself. Even if your computer is infected, the keys never leave the device.

A seed phrase is a list of 12 or 24 ordinary words that can recreate all the keys of a wallet. Whoever has the words has the bitcoin, so write them on paper or metal and never type them into a website.

An exchange's attempt to show it holds the customer coins it owes.

Hot: keys on an internet-connected device. Cold: keys kept offline.