All 15 Core Node.js Modules questions
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What does the node:crypto module provide, and what's the difference between hashing and encryption?

Intermediate

Answer

crypto provides hashing (createHash), symmetric/asymmetric encryption, HMAC signing, and secure random generation. Hashing is one-way, producing a fixed-size fingerprint that can't be reversed; encryption is reversible, transforming data into ciphertext decryptable back to plaintext given the correct key.
const hash = crypto.createHash('sha256').update('some data').digest('hex');
const cipher = crypto.createCipheriv('aes-256-gcm', key, iv);
Real-world example A file-integrity checker computes a SHA-256 hash to verify a download wasn't corrupted, while a separate feature encrypts stored API credentials with AES-256-GCM so they can be decrypted later.

Common follow-ups: Why is crypto.randomBytes() preferred over Math.random() for security-sensitive values?;What does 'GCM' in AES-256-GCM provide beyond basic encryption?

Security;Authentication & Authorization (JWT OAuth Passport)
All 15 Core Node.js Modules questions