HTML5 <!DOCTYPE> Declaration
The <!DOCTYPE> declaration for THML5
Example
<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
</head>
<body>
The content of the document......
</body>
</html>
Try it yourself in Notepad or Dreamweaver by coping and pasting the code above.
Example
<!DOCTYPE html><html>
<head>
<title>Title of the document</title>
</head>
<body>
The content of the document......
</body>
</html>
Browser Support
The <!DOCTYPE> declaration is supported in all major browsers.
Definition and Usage
The <!DOCTYPE> declaration must be the very first thing in your HTML5 document, before the <html> tag.
The <!DOCTYPE> declaration is not an HTML tag; it is an instruction to the web browser about what version of HTML the page is written in.
In HTML 4.01, all <!DOCTYPE> declarations require a reference to a DTD, because HTML 4.01 was based on SGML.
HTML5 is not based on SGML, and therefore does not require a reference to a DTD.
Tip: Always add the <!DOCTYPE> declaration to your HTML documents, so that the browser knows what type of document to expect.
Differences Between HTML 4.01 and HTML5
There are three different <!DOCTYPE> declarations in HTML 4.01. In HTML5 there is only one:
<!DOCTYPE html>
Tips and Notes
Note: The <!DOCTYPE> tag does not have an end tag.
Tip: The <!DOCTYPE> declaration is NOT case sensitive


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