The Public Key
What Is a Public Key?
A public key is a piece of publicly available information on the blockchain that belongs to a specific user or wallet. It allows other parties to send cryptocurrency or tokens securely. In the traditional banking world, a public key is most similar to a bank account number.
What Is the Role of a Public Key?
Public keys serve several important functions:
- Receiving assets: To send cryptocurrency or tokens to someone, the sender only needs to know the recipient’s public key.
- Verifying transactions: When a sender signs a transaction using their private key, the blockchain network uses the corresponding public key to check the digital signature and confirm that the transaction is valid.
- Ensuring security: Even though the public key is visible to everyone, it’s practically impossible to reverse-engineer the private key from it. This means the public key helps with verifying transactions and identifying the sender, without exposing their real identity.
Main Differences between a Private Key and a Public Key
| Private Key | Public Key | |
|---|---|---|
| Visibility | Secret, must not be shared | Public, can be freely shared |
| Function | Used to sign transactions and manage assets | Used to verify transactions and receive assets |
| Security Risk | Losing it means losing access to your assets | Publicly visible, but still requires some privacy precautions |
Security Considerations
Even though public keys are meant to be shared, it’s still important to handle them with care. Here are a few things to keep in mind:
- Ensure authenticity: Always share your public key through secure and trusted channels. This helps prevent attackers from replacing your key with their own.
- Avoid fake QR codes: If you’re sharing your public key via a QR code, make sure to generate it with a secure and verified app to avoid tampering.
- Be mindful of metadata: Reusing the same public key over and over can make it easier for others to track your transaction history. This may reduce your privacy and overall security.
In short, a public key isn’t secret, but how and where you share it can have a big impact on your safety and privacy.
