blockmindset
Concept comparison

Hashing vs Encryption

Hashing proves integrity without recovery; encryption hides data so an authorized party can recover it.

Dimension
Hashing
Encryption
Direction
One-way: input to digest.
Two-way with a key: plaintext to ciphertext and back.
Takeaway: Do not say a hash is encrypted data. It is not meant to be decrypted.
Blockchain use
Block IDs, Merkle roots, mining targets, and integrity checks.
Wallet backups, private communication, and key wrapping around the chain.
Takeaway: Public blockchains mostly use hashes and signatures, not encrypted ledgers.
Security goal
Detect changes and make reverse lookup impractical.
Keep content confidential from anyone without the key.
Takeaway: Integrity and confidentiality are different properties.
Common mistake
Assuming a hash can be decoded.
Assuming encrypted data proves who sent it.
Takeaway: Signatures, hashes, and encryption solve different jobs.

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