Re: HTTP/0.9

    Is there a document that describes HTTP/0.9?

    What I am particularly interested in is the format of the request
    line (there were no headers, right?).

RFC1945 documents HTTP/0.9.  The format of the request is (was):

       Simple-Request  = "GET" SP Request-URI CRLF

and the response format was:

       Simple-Response = [ Entity-Body ]

with no version numbers, no response status line, and no request or
response headers.  

Based on my reading of some server source code, I believe that instead
of a Content-Type response header, the older browsers apparently
understood a tag like <PLAINTEXT> to indicate non-HTML responses.
(Someone will no doubt correct me if I'm wrong.)

-Jeff