📄 html_whyusehtml4.asp@output=print
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<title>Why Use HTML 4</title>
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<p>From <b>http://www.w3schools.com</b> (Copyright Refsnes Data)</p>
<h1>Why use HTML 4.0?</h1>
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<h2>HTML 3.2 Was Very Wrong !</h2>
<p>The original HTML was <b>never intended</b> to contain tags for <b>formatting</b>
a document. HTML tags were intended to define the <b>content</b> of the document
like:</p>
<p><p>This is a paragraph</p></p>
<p><h1>This is a heading</h1></p>
<p>When tags like <font> and color attributes were added to the HTML 3.2 specification,
it started a <b>nightmare</b> for web developers. Development of large web sites where
fonts and color information had to be added to every single Web page, became a
long, expensive and unduly painful process.</p>
<hr />
<h2>What is so Great About HTML 4.0 ?</h2>
<p>In HTML 4.0 <b>all formatting can be removed</b> from the HTML document and
stored in a
separate style sheet.</p>
<p>Because HTML 4.0 separates the presentation from the document
structure, we have what we always needed: Total control of presentation
layout without messing up the document content.</p>
<hr />
<h2>What Should You do About it ?</h2>
<p>Do not use presentation attributes inside your HTML tags if you can avoid it.
Start using styles! Please read our <a target="_top" href="../css/default.asp">CSS
tutorial</a> to learn about style sheets.</p>
<p>Do not use deprecated tags. Visit our complete <a href="html_reference.asp">
HTML 4.01 Reference</a> to see which tags and attributes that are deprecated.</p>
<hr />
<h2>Prepare Yourself for XHTML</h2>
<p>XHTML is the "new" HTML.
The most important thing you can do is to start writing valid HTML 4.01. Also
start writing your tags in lower case. Always close your tag elements. Never end
a paragraph without </p>.</p>
<p><b>NOTE: </b> The official HTML 4.01 recommends the use of lower case tags.</p>
<p>If you want to read about how this web site was converted to XHTML, please
visit our <a href="../xhtml/default.asp">XHTML tutorial</a>.</p>
<hr />
<h2>Validate Your HTML Files as HTML 4.01</h2>
<p>An HTML document is validated against a Document Type Definition (DTD).
Before an HTML file can be properly validated, a correct DTD must be added as
the first line of the file.</p>
<p>The HTML 4.01 Strict DTD includes elements and attributes that have
not been deprecated or do not appear in framesets:</p>
<table class="ex" cellspacing="0" border="1" width="100%">
<tr>
<td align="left"><pre><!DOCTYPE HTML PUBLIC
"-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd"></pre>
</td>
</tr>
</table>
<p>The HTML 4.01 Transitional DTD includes everything in the strict DTD plus deprecated elements and attributes:</p>
<table class="ex" cellspacing="0" border="1" width="100%">
<tr>
<td align="left"><pre><!DOCTYPE HTML PUBLIC
"-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd"></pre>
</td>
</tr>
</table>
<p>The HTML 4.01 Frameset DTD includes everything in the transitional DTD
plus frames as well:</p>
<table class="ex" cellspacing="0" border="1" width="100%">
<tr>
<td align="left"><pre><!DOCTYPE HTML PUBLIC
"-//W3C//DTD HTML 4.01 Frameset//EN"
"http://www.w3.org/TR/html4/frameset.dtd"></pre>
</td>
</tr>
</table>
<br />
<hr />
<h2>Test Your HTML With the W3C Validator</h2>
<form method="get" action="http://validator.w3.org/check" target="_blank">
Input your page address in the box below<br />
(like http://www.w3schools.com/)<br />
<input name="uri" size="50" />
<br /><br />
<input type="submit" value="Validate the page" />
</form>
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<p>From <b>http://www.w3schools.com</b> (Copyright Refsnes Data)</p>
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