Re: Valid GIF

From: Terje Bless (
Date: Tue, Nov 09 1999

Message-Id: <>
Date: Wed, 10 Nov 1999 01:31:44 +0100
From: Terje Bless <>
To: W3C Validator <>
Subject: Re: Valid GIF

On 09.11.99 at 13:02, Vivek Shankar <> wrote:

>The code for the image seems to be inapprporiate the 'gif extension is
>missing. Please correct me if I am wrong.

Ok. :-)

The filename extension is left out to let the server negotiate with the
client whether to return a GIF file or a PNG file. PNG is the preferred
format but not all clients can handle it so there has to be a fallback to
the GIF files. This will of course fail if the server running the validator
does not have content negotiation enabled.