- From: Lachlan Hunt <lachlan.hunt@iinet.net.au>
- Date: Fri, 24 Sep 2004 23:57:36 +1000
- To: Harshad <harshad@gsimail.com>
- CC: www-validator@w3.org
Harshad wrote: > no document type declaration; implying "<!DOCTYPE HTML SYSTEM>" It means that your document has not started with a DOCTYPE [1], which all HTML documents should have. If you don't include a doctype, the document is invalid, and modern UAs just treat it as tag soup, meaning they try their best to handle whatever they get. Most people these days should be using either HTML 4.01 Strict or Transitional doctypes. I don't recomend you use XHTML just yet, as it is not supported by all UAs. Pick the DOCTYPE based on the which elements you've used. If you've used any deprecated elements [2], than you need to use Transitional. If not, then I recommend that you use Strict. If you've used any elements not listed in [2], then they are likely to be proprietary extensions, which should not be used anyway. By using a DOCTYPE, modern UAs will parse and render the document in a standards compliant mode. If you omit the doctype, the rendering will be in quirks mode, which essentially means that they attempt to be bugwards compatible with the ancient IE and Netscape 4.x parsing and rendering. This process is called DOCTYPE sniffing. I recommend you follow the standards and use a correct doctype. [1] http://www.w3.org/QA/2002/04/valid-dtd-list.html [2] http://www.w3.org/TR/html401/index/elements.html -- Lachlan Hunt http://lachy.id.au/ http://getfirefox.com/ Rediscover the Web http://spreadfirefox.com/ Igniting the Web
Received on Friday, 24 September 2004 13:58:17 UTC