Back To Website Design Forum

First line of HTML code <!DOCTYPE HTML PUBLIC .

  • User #2
  • Student
  • Student
  • No Avatar
  • Joined: 07 Apr 2005
  • Posts: 89
  • Status: Offline

Post January 27th, 2006, 12:53 am

What does that code do?
this one below.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

Do I need it?
What happends if I don't use this code?
Can I miss-use?
Is it important?

Thank you.
  • Anonymous
  • Bot
  • No Avatar
  • Joined: 25 Feb 2008
  • Posts: ?
  • Loc: Ozzuland
  • Status: Online

Post January 27th, 2006, 12:53 am

  • ATNO/TW
  • Super Moderator
  • Super Moderator
  • User avatar
  • Joined: 28 May 2003
  • Posts: 21846
  • Loc: Pittsburgh PA
  • Status: Offline

Post January 27th, 2006, 1:11 am

Your document will work without it. You could do

Line number On/Off
Code: Select all
<html>
<head>
<title>My Web Page</title>
</head>
<body>
Hello World
</body>
</html>

and the page will display just fine in most browsers, but it's not correct.

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
is what's know as a "document type declaration (or definition)" (DTD). In essence it identifies to the browser the type of code that is being used in the document. When declaring a doctype, it is then your responsibility as a designer to code the page to the specifications you have "declared" you are using in the doctype. In your example, you are declaring to the browser that you will be writing your code to HTML 4.01 transitional specifications and that is what it is expecting. If you falter from those "expectations" then your code may become considerd as "invalid" and may not display correctly in some browsers.

This is where things start to get a little confusing. The transitional doctype was institituted to allow a transitional period for designers to migrate from older coding standards to newer coding standards. An alternative to a "transitional" doctype would be a "strict" doctype.

In the example you have provided the distinction would be that for a "strict" doctype to be valid and display correctly, then you must write the code for your pages specifically to HTML 4.01 standards, whereas using a "transitional "doctype would allow you to use depracated (i.e. obsolete) code from say perhaps, HTML 4.0 or HTML 3.2 and, although it's planned to eventually be elliminated would at least still work for the time being.

An example would be <font> tags. Very old coding practice and now depricated and has been replaced by using style instead.


For more on doctype declarations (a.k.a. DTD's) go here
http://www.w3schools.com/tags/tag_doctype.asp

(one of these days I need to do a complete tutorial on this.)
"The web is a dominatrix. Every where I turn, I see little buttons ordering me to Submit."
Boasting Rights Sports Forum || Nuclear Services - www.alaron-nuclear.com

Page 1 of 1

Post Information

  • Total Posts in this topic: 2 posts
  • Moderator: Moderator Team
  • Users browsing this forum: No registered users and 72 guests
  • You cannot post new topics in this forum
  • You cannot reply to topics in this forum
  • You cannot edit your posts in this forum
  • You cannot delete your posts in this forum
  • You cannot post attachments in this forum
 
 

© Unmelted Enterprises 1998-2009. Driven by phpBB © 2001-2009 phpBB Group.