Signing devices

In plain words

A signing device (often called a hardware wallet) keeps your secret keys inside a chip that never gives them up. Your phone or computer prepares a payment; the device shows you what it really says — how much, to where — and signs only when you press approve. A virus on your computer can ask, but it can't sign. Some models never plug in at all, passing payments by QR code or memory card.

Why it matters

• Keeps the money away from the malware — keys never live on an internet-connected machine.
• The device's screen is the truth; a computer's screen can lie.
• Cheap insurance next to what it protects.

Not to be confused with

• Wallet apps — software that watches your coins and drafts payments; the device only holds keys and signs.

Go deeper

• Hardware wallets
• Keys & addresses
• Multisig