Cryptography
cryptography
security
What is Encryption?
Definition
Encryption transforms readable data (plaintext) into unreadable ciphertext using an algorithm and a key. Only someone with the correct key can decrypt and read the original data. Common algorithms include AES (symmetric) and RSA (asymmetric).
Why It Matters
Encryption protects data at rest (disk encryption, database encryption) and in transit (HTTPS, VPN, messaging). It is legally required for handling sensitive data like medical records (HIPAA) and payment information (PCI DSS).
Frequently Asked Questions
What is the difference between encryption and hashing?
Encryption is reversible — you can decrypt ciphertext back to plaintext with the correct key. Hashing is one-way — you cannot recover the original data from a hash. Use encryption to protect data you need to read later; use hashing for verification (passwords, checksums).