Encryption

Definition

Encryption transforms readable data into a protected form that requires the correct key to recover.

How it works

Encryption protects data on the move — like traffic between a browser and your site — and at rest on a disk. It delivers confidentiality, but only as part of a bigger picture: keys have to be managed well, identities verified, and software kept current. Strong encryption around weak passwords is a locked door with the key under the mat.

Example: TLS encrypts application data sent between a browser and an HTTPS website.

Often confused: Encoding just changes how data is written, and anyone can reverse it; hashing is one-way by design. Only encryption is built to be locked and unlocked with a key.

Related terms

• Cipher
• HTTPS
• SSL certificate
• Transport Layer Security (TLS)

Learn more from Bitfoo

• Check HTTPS and redirects

Sources

• NIST Computer Security Resource Center Glossary
• IETF RFC 8446: The Transport Layer Security Protocol Version 1.3

Last reviewed 2026-07-19.