Appendix B. Common HTTP Headers
Here we look at a series of often-used headers, whether they are request or response headers, and how they can be used.
Header | Request | Response | Notes |
---|---|---|---|
|
yes |
This shows the formats, with an indication of preference, that the requesting client can understand. Closely related are the additional headers |
|
|
yes |
This is free-form information to prove a userâs identity. This is used in basic authentication, digest authentication, OAuth, and so on; each has their own format of exactly what goes in the header. |
|
|
yes |
Cookies are key/value pairs sent with each request, separated by a semicolon. This is the sister header to |
|
|
yes |
yes |
Any request or response with body content should also have the |
|
yes |
yes |
Any request or response with body content should include the |
|
yes |
This is an identifier for the version of the resource that is being returned. If the client caches the resource, this information can be used with |
|
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