HTTP Reference

The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed, collaborative, and hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web.

Hypertext is structured text that uses logical links (hyperlinks) between nodes containing text. HTTP is the protocol to exchange or transfer hypertext.

Table of content
HTTP
Identifying resources on the Web
Data URIs
Introduction to MIME Types
Complete list of MIME Types
Choosing between www and non-www URLs
Basics of HTTP
Overview of HTTP
Evolution of HTTP
HTTP Messages
A typical HTTP session
Connection management in HTTP/1.x
Protocol upgrade mechanism
Content Security Policy (CSP)
HTTP Public Key Pinning (HPKP)
HTTP Strict Transport Security (HSTS)
Cookie security
X-Content-Type-Options
X-Frame-Options
X-XSS-Protection
Mozilla web security guidelines
HTTP access control (CORS)
HTTP authentication
HTTP caching
HTTP compression
HTTP conditional requests
HTTP content negotiation
HTTP cookies
HTTP range requests
HTTP redirects
HTTP specifications
HTTP headers
Accept
Accept-Charset
Accept-Encoding
Accept-Language
Accept-Ranges
Access-Control-Allow-Credentials
Access-Control-Allow-Headers
Access-Control-Allow-Methods
Access-Control-Allow-Origin
Access-Control-Expose-Headers
Access-Control-Max-Age
Access-Control-Request-Headers
Access-Control-Request-Method
Age
Allow
Authorization
Cache-Control
Connection
Content-Disposition
Content-Encoding
Content-Language
Content-Length
Content-Location
Content-Range
Content-Security-Policy
Content-Security-Policy-Report-Only
Content-Type
Cookie
Cookie2
DNT
Date
ETag
Expect
Expires
Forwarded
From
Host
If-Match
If-Modified-Since
If-None-Match
If-Range
If-Unmodified-Since
Keep-Alive
Large-Allocation
Last-Modified
Location
Origin
Pragma
Proxy-Authenticate
Proxy-Authorization
Public-Key-Pins
Public-Key-Pins-Report-Only
Range
Referer
Referrer-Policy
Retry-After
Server
Set-Cookie
Set-Cookie2
SourceMap
Strict-Transport-Security
TE
Timing-Allow-Origin
Tk
Trailer
Transfer-Encoding
Upgrade-Insecure-Requests
User-Agent
Vary
Via
WWW-Authenticate
Warning
X-Content-Type-Options
X-DNS-Prefetch-Control
X-Forwarded-For
X-Forwarded-Host
X-Forwarded-Proto
X-Frame-Options
X-XSS-Protection
HTTP request methods
CONNECT
DELETE
GET
HEAD
OPTIONS
PATCH
POST
PUT
HTTP response status codes
100 Continue
101 Switching Protocols
200 OK
201 Created
202 Accepted
203 Non-Authoritative Information
204 No Content
205 Reset Content
206 Partial Content
300 Multiple Choices
301 Moved Permanently
302 Found
303 See Other
304 Not Modified
307 Temporary Redirect
308 Permanent Redirect
400 Bad Request
401 Unauthorized
403 Forbidden
404 Not Found
405 Method Not Allowed
406 Not Acceptable
407 Proxy Authentication Required
408 Request Timeout
409 Conflict
410 Gone
411 Length Required
412 Precondition Failed
413 Payload Too Large
414 URI Too Long
415 Unsupported Media Type
416 Range Not Satisfiable
417 Expectation Failed
426 Upgrade Required
428 Precondition Required
429 Too Many Requests
431 Request Header Fields Too Large
451 Unavailable For Legal Reasons
500 Internal Server Error
501 Not Implemented
502 Bad Gateway
503 Service Unavailable
504 Gateway Timeout
505 HTTP Version Not Supported
511 Network Authentication Required
CSP: base-uri
CSP: block-all-mixed-content
CSP: child-src
CSP: connect-src
CSP: default-src
CSP: font-src
CSP: form-action
CSP: frame-ancestors
CSP: frame-src
CSP: img-src
CSP: manifest-src
CSP: media-src
CSP: object-src
CSP: plugin-types
CSP: referrer
CSP: report-uri
CSP: require-sri-for
CSP: sandbox
CSP: script-src
CSP: style-src
CSP: upgrade-insecure-requests
CSP: worker-src