HTTP1.1 header字段定义

参考RFC2616: http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.40 

本文只是学习摘要,列出所有header字段，并用颜色进行分类（按应用场景）

1.  Accept
2.  Accept-Charset
3.  Accept-Encoding
4.  Accept-Language
5.  Accept-Ranges
6.  Age
7.  Allow
8.  Authorization
9.  Cache-Control
10.  Connection
11.  Content-Encoding
12.  Content-Language
13.  Content-Length
14.  Content-Location
15.  Content-MD
16.  Content-Range
17.  Content-Type
18.  Date
19.  ETag
20.  Expect
21.  Expires
22.  From
23.  Host
24.  If-Match
25.  If-Modified-Since
26.  If-None-Match
27.  If-Range
28.  If-Unmodified-Since
29.  Last-Modified
30.  Location
31.  Max-Forwards
32.  Pragma
33.  Proxy-Authenticate
34.  Proxy-Authorization
35.  Range
36.  Referer
37.  Retry-After
38.  Server
39.  TE
40.  Trailer
41.  Transfer-Encoding
42.  Upgrade
43.  User-Agent
44.  Vary
45.  Via
46.  Warning
47.  WWW-Authenticate

应用分类：Request header fields:

request-header = Accept                  
                      | Accept-Charset   
                      | Accept-Encoding     
                      | Accept-Language       
                      | Authorization        
                      | Expect                
                      | From                 
                      | Host                  
                      | If-Match                
                      | If-Modified-Since      
                      | If-None-Match         
                      | If-Range             
                      | If-Unmodified-Since    
                      | Max-Forwards           
                      | Proxy-Authorization   
                      | Range                   
                      | Referer             
                      | TE                     
                      | User-Agent