What is Public Key?
A public key is derived from a private key via elliptic-curve multiplication. It can be shared safely and is used to verify digital signatures produced by the corresponding private key. In Bitcoin, addresses are derived from public keys.
Why Public Key matters
Understanding Public Key is part of building a solid mental model of how Bitcoin, blockchain and Web3 systems actually work. Concepts in the Cryptography category sit at the foundation of the broader stack — get them right and the rest is far easier.
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Related terms
- Private Key — The secret number that authorises spending from an address.
- Digital Signature — A cryptographic proof that the holder of a private key authorised a message.
- Address (Bitcoin / Crypto Address) — A public destination for receiving cryptocurrency.
More cryptography terms
- ECDSA — Elliptic Curve Digital Signature Algorithm.
- Hash Function — A deterministic function mapping arbitrary input to fixed-size output.
- Merkle Root — The single hash summarising all transactions in a block.
- Merkle Tree — A binary tree of hashes used to summarise data efficiently.
- SHA-256 — The hash function Bitcoin uses everywhere.
- Zero-Knowledge Proof — Proving you know something without revealing what it is.
- Schnorr Signature — A signature scheme enabling key aggregation.
- Merkle Proof — Compact proof that a transaction is in a block.
Keep exploring
Continue with the full blockchain glossary — 136 terms in total — or read the developer blog and FAQ for deeper context.