SSL/TLS
Cryptographic protocols that encrypt data in transit between client and server. TLS is the modern successor to SSL. The 'S' in HTTPS.
What is SSL/TLS?
Cryptographic protocols that encrypt data in transit between client and server. TLS is the modern successor to SSL. The 'S' in HTTPS.
SSL/TLS is a intermediate-level concept that sits in the Security Architecture area of system design. Engineers reach for it whenever they need to reason about real-world trade-offs in that space — not just for textbook correctness, but because real production systems at companies like Netflix, Amazon, and Google make these decisions every day.
If you want to go deeper than this definition — with diagrams, code, and a quiz to lock it in — work through the "SSL/TLS" lesson linked below. It walks through the why, the mechanism, the trade-offs, and how the giants actually use it in production.
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See also
Related glossary terms you might want to look up next.
HTTP
The protocol powering the web. A request-response model where clients ask for resources and servers respond. Stateless by design.
TCP
A reliable transport protocol that guarantees data arrives in order and without errors. It uses a three-way handshake to establish connections.
OAuth
An authorization framework that lets users grant third-party apps limited access to their accounts without sharing passwords. Powers 'Sign in with Google.'