HTTP Pocket Reference

Requests

Given the following URL:

http://hypothetical.ora.com:80/

The browser interprets the URL as follows:

http://

Use HTTP, the Hypertext Transfer Protocol.

hypothetical.ora.com

Contact a computer over the network with the hostname of hypothetical.ora.com.

:80

Connect to the computer at port 80. The port number can be any legitimate IP port number: 1 through 65535, inclusively.^[1] If the colon and port number are omitted, the port number is assumed to be HTTP’s default port number, which is 80.

/

Anything after the hostname and optional port number is regarded as a document path. In this example, the document path is /.

So the browser connects to hypothetical.ora.com on port 80 using the HTTP protocol. The message that the browser sends to the server is:

GET / HTTP/1.1
Accept: image/gif, image/x-xbitmap, image/
    jpeg, image/pjpeg, */*
Accept-Language: en-us
Accept-Encoding: gzip, deflate
User-Agent: Mozilla/4.0 (compatible; MSIE
    5.01; Windows NT)
Host: hypothetical.ora.com
Connection: Keep-Alive

Let’s look at what these lines are saying:

1. The first line of this request (GET / HTTP/1.1) requests a document at / from the server. HTTP/1.1 is given as the version of the HTTP protocol that the browser uses.

2. The second line tells the server what kind of documents are accepted by the browser.

3. The third line indicates that the preferred language is English. This header allows the client to specify a preference for one or more languages, in the event that a server has the same document in multiple languages. ...