AJAX - The Complete Reference

594 Part IV: Appendixes

Request Header Description Examples

Accept-Language Lists the languages preferred by

the browser and can be used by the

server to pass back the appropriate

language data. Similar to the

other Accept related headers “q”

parameters are allowed with this

header.

Accept-Language: en-

us,en;q=0.5

Authorization Typically used to indicate the

authorization type and encoded

user id : password if the user is

returning authorization information.

Note that there is nothing to prevent

decoding such values unless this

transmission is encrypted as with

SSL connections.

Authorization: Basic QWxhZGRp

bjpvcGVuIHNlc2FtZQ==

Cookie Passes any set cookie(s) for the

resource server or domain being

requested. Note: This header is not

part of the HTTP 1.1 specification,

but it is so commonly sent it is

included here.

Cookie: PREF

ID=d771c1ef8465c3a5

Expect Indicates that particular server

behaviors are required. This is

found in a situation where a client

wants to wait for a server response

code 100, indicating the request

should continue before sending

request body.

Expect: 100-continue

From Should provide the e-mail address

of the person who controls the

user-agent making the request. This

header is in the specification but is

rarely if ever seen outside of some

bot requests because of privacy

implications.

From: [email protected]

Host Indicates the host and port of the

server to which the request is being

made. It is extremely important in a

server that is running many domain

names at once as virtual servers.

A trailing port number can be used

as well, separated by a colon;

otherwise, the default value of 80

for HTTP requests is used.

Host: ajaxref.com

TABLE B-5 HTTP 1.1 Request Headers (continued)