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[>_] Web Fundamentals/HTTP Headers That Matter6 tasks

[>_] ROOM · Web

HTTP Headers That Matter

Read request and response headers for a living: who sets each one, who trusts it, how caching and content negotiation work, and how to audit security headers.

Beginner 6 tasks ~3h 25m +150 Rep

Part of Web Fundamentals

EARN UP TO +150 Rep

Beginner × 6 tasks+10 avg

Room bonus+90

Rep counts toward your Web rank

// about

About this room

Headers decide how a browser treats a response, how long a cache keeps it and which protections are switched on. You start with the headers a client sends and why none of them can be trusted for a security decision, then read the headers a server sends back. You work through content negotiation, caching with Cache-Control, ETag and 304, and the security headers from HSTS to Content-Security-Policy. The room ends with a header audit of six hosts of a small online shop, written up as a list of fixes.

Room tasks

6 tasks

01Lesson 01Request Headers: What the Client Says About Itself 30 min· +10 RepNot started

02Lesson 02Response Headers: What the Server Says About the Answer 30 min· +10 RepNot started

03Lesson 03Content Negotiation: Type, Language and Compression 30 min· +10 RepNot started

04Lesson 04Caching Headers: Cache-Control, ETag and 304 35 min· +10 RepNot started

05Lesson 05Security Headers: HSTS, CSP and Their Neighbours 35 min· +10 RepNot started

06Lesson 06Guided Lab: Audit the Headers of a Small SiteFinal · +90 bonus 45 min· +100 RepNot started

Skills & topics

web fundamentals HTTP DNS URL headers cookies sessions HTTPS TLS curl

Each task’s Rep is set individually — beginner tasks average +10. The +90 room bonus unlocks at 100%.