HTTP and Web

HTTP versions, methods, status codes, headers and cookies.

• What is the difference between HTTP and HTTPS?GEN-03-001
• What are HTTP methods (GET, POST, PUT, DELETE…)?GEN-03-002
• What is an HTTP status code; what do the 2xx, 3xx, 4xx and 5xx classes describe?GEN-03-003
• What is an HTTP Header?GEN-03-004
• What is the Host Header?GEN-03-005
• What is the User-Agent header?GEN-03-006
• What is a cookie; what is the difference between the Cookie and Set-Cookie headers?GEN-03-007
• What is HTTP compression?GEN-03-008
• What are the parts of a URL (scheme, host, path, query string)?GEN-03-009
• What is the difference between HTTP/1.1 and HTTP/2?GEN-03-010
• What are HTTP/3 and QUIC?GEN-03-011
• What is the difference between the 301, 302, 307 and 308 redirect codes?GEN-03-012
• What is the Accept-Language header?GEN-03-013
• What are the Referer header and Referrer-Policy?GEN-03-014
• What are the Secure, HttpOnly and SameSite cookie attributes?GEN-03-015
• What is HTTP keep-alive?GEN-03-016
• What is WebSocket?GEN-03-017
• What is the difference between GZIP and DEFLATE?GEN-03-018
• What is a MIME type (Content-Type)?GEN-03-019
• What is HTTP caching; what does the Cache-Control header do?GEN-03-020
• What is CORS; what is a preflight (OPTIONS) request for?GEN-03-021
• What are HTTP security headers?GEN-03-022
• What is Content-Security-Policy (CSP)?GEN-03-023
• What is X-Frame-Options?GEN-03-024
• What is mixed content?GEN-03-025
• What is gRPC?GEN-03-026
• What is the difference between a multipart form and a URL-encoded form?GEN-03-027
• What is X-Content-Type-Options: nosniff?GEN-03-028
• What is URL percent-encoding?GEN-03-029
• What is 421 Misdirected Request?GEN-03-030