Question 1

What can response headers tell me?

Accepted Answer

Headers reveal the web server type, caching policy, security hardening (HSTS, CSP) and encoding — everything negotiated before the client renders anything.

Question 2

Why is my URL redirected?

Accepted Answer

The usual cases are HTTP upgraded to HTTPS and the bare domain normalised to www. The redirect chain shows every hop on the way to the final page.

Question 3

Which security headers matter most?

Accepted Answer

Strict-Transport-Security, Content-Security-Policy and X-Content-Type-Options. Modern sites are worth adding them if missing.