Last updated 14 July 2026 · reviewed for accuracy

HTTP & TLS

HTTP is beautifully simple (a text request, a numbered response) and totally public. TLS wraps it in an encrypted envelope after a brief handshake where the server proves its identity with a certificate and both sides agree on keys. That padlock in your browser is this lesson.

We decode one HTTPS connection end to end: what an eavesdropper sees (very little) and what they can still infer (more than you’d think).