Understanding DOCTYPES and Effects on Browser Layout

**nirdesh** · 05-23-2012, 11:36 AM

HTML 4.01 has three document types: strict, transitional, and frameset. XHTML 1.1 has one document type, but XHTML 1.0 has three document types, like HTML 4.01. Only one document type definition (DTD) appears in the HTML document, using any one of the following:

HTML 4.01 Strict DTD:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">

HTML 4.01 Transitional DTD:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/1999/REC-html401-19991224/loose.dtd">

HTML 4.01 Frameset DTD:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN"
" http://www.w3.org/TR/1999/REC-html401-19991224/frameset.dtd">

XHTML 1.0 Strict DTD:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

XHTML 1.0 Transitional DTD:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

XHTML 1.0 Frameset DTD:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">

XHTML 1.1 DTD:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">

Here's a basic page with the XHTML 1.1 DTD and the required head, body, and html tags.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html>
<head>
<title>XHTML DTD</title>
</head>
<body>
<p>XHTML requires having a DTD in every document otherwise it won't pass muster with the validators.</p>
</body>
</html>

**XhinZ** · 06-12-2012, 07:40 PM

With more and more browsers being HTML 5 Compatible you can just use
<!DOCTYPE HTML> instead of old version based DOCTYPES, the HTML 5 version is also compatible with the 4 major browsers(crome, mozilla, saffari and opera) and many mobile browsers!

**venus11** · 07-21-2012, 06:54 PM

Thankyou very much for the information on Understanding DOCTYPES and Effects on Browser Layout . well this looks abit difficult to see , but let me try , im gonna do it . and you keep on doing this .

**benmoriz** · 09-10-2012, 06:45 AM

With more and more browsers being HTML 5 Compatible you can just use
<!DOCTYPE HTML> instead of old version based DOCTYPES, the HTML 5 version is also compatible with the 4 major browsers(crome, mozilla, saffari and opera)Thankyou very much for the information on Understanding DOCTYPES and Effects on Browser Layout . well this looks abit difficult to see

**njtboy** · 09-14-2012, 01:14 AM

HTML 4.01 has three document types: strict, transitional, and frameset. XHTML 1.1 has one document type, but XHTML 1.0 has three document types, like HTML 4.01. Only one document type definition (DTD) appears in the HTML document, using any one of the following:

HTML 4.01 Strict DTD:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">

HTML 4.01 Transitional DTD:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/1999/REC-html401-19991224/loose.dtd"

With more and more browsers being HTML 5 Compatible you can just use
<!DOCTYPE HTML> instead of old version based DOCTYPES, the HTML 5 version is also compatible with the 4 major browsers(crome, mozilla, saffari and opera)Thankyou very much for the information on Understanding DOCTYPES and Effects on Browser Layout .