Comparisons
HTTP Side-by-Side
Confused by similar-sounding HTTP concepts? These comparisons cut through the ambiguity with concrete differences, use cases, and decision rules.
301 vs 302 Redirects
Understand the difference between 301 Moved Permanently and 302 Found redirects. Learn when to use each, how browsers cache them, and their SEO implications.
304 Not Modified vs 200 OK
Understand when servers return 304 Not Modified instead of 200 OK. Learn how conditional requests, ETags, and Last-Modified headers enable efficient HTTP caching.
401 vs 403: Authentication vs Authorization
Understand the difference between 401 Unauthorized and 403 Forbidden. Learn when each status code applies, common mistakes, and how to use them correctly in APIs.
Cookie-Based vs Session-Based Authentication
Compare cookie-based and session-based authentication. Understand where state lives, security tradeoffs, scalability implications, and when to use each approach.
CORS vs CSP
Understand the difference between CORS and Content Security Policy. Both are browser security mechanisms but they protect against completely different threats.
GET vs POST
Understand the fundamental differences between GET and POST HTTP methods. Learn about safety, idempotency, caching, request bodies, and when to use each.
HTTP/1.1 vs HTTP/2
Compare HTTP/1.1 and HTTP/2. Understand multiplexing, header compression, server push, and when upgrading to HTTP/2 actually improves performance.
Permissions-Policy vs Feature-Policy
Understand the differences between Permissions-Policy and Feature-Policy headers. Compare syntax changes for geolocation, microphone, camera directives and learn how to migrate.
PUT vs PATCH
Understand the difference between PUT and PATCH HTTP methods. Learn when to use full replacement vs partial update, and how each affects idempotency and API design.