BitcoinMadeClear

What is a private key?

A private key is secret information used to approve spending bitcoin. Your wallet uses it to make a digital signature that other computers can check without seeing the key itself.

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What does that mean for you?

Think of approval authority rather than a password sent to a website. A signature is made for a payment. The secret used to make it is meant to stay private.

A wallet may manage keys for you, or a service may control them. The key is different from the address you share to receive a payment and different from an account login.

What is a private key?Private key: Secret approval authority. Signature: Approval others can check. Payment: Must also satisfy network rules.Private keySecret approval authoritySignatureApproval others can checkPaymentMust also satisfy network rules
Private key: Secret approval authority. Signature: Approval others can check. Payment: Must also satisfy network rules.

Can you picture an example?

Imagine someone asks for your private key so they can send you bitcoin. They do not need it to send a payment. Giving it away could give them the ability to spend the amount it controls.

What should you remember?

Many wallets use recovery words to rebuild their keys. Those words also need protection. Understanding the distinction is enough here; this guide does not describe key mathematics or tell you to handle raw keys manually.

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