The document type declaration - DOCTYPE is associates XML or Standard Markup Languages e.g. HTML with a DTC (document type definition)
HTML5 DOCTYPE Syntax: <!DOCTYPE html>
HTML4 DOCTYPE Syntax: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
As you can see from the syntax, the DOCTYPE for HTML5 is rather the shortest declaration compared to HTML4 or other XHTML declarations due to the lack of references to a DTD like we usually have a DTD URL as an attribute.
⚡️ Note: HTML5 doctype is case-insensitive! so <!doctype html> is very well valid.
What is the advantage of using HTML5 doctype?
HTML5 is the 5th version of HTML standard, you get a lot of new features with it such as - rich media support, Forms 2.0, Canvas, Audio and Video Support, Geo Location, Micro Data and much more.
Example:<!DOCTYPE html>
<html>
<head>
<title>HTML5 Doctype example!</title>
</head>
<body>
</body>
</html>
To validate your webpage is following HTML5 syntax and doctype correctly you can use https://validator.w3.org/ w3c Markup validator tool!
Summary:
1)What is the HTML5 Doctype? <!DOCTYPE html>
2)Is HTML5 Doctype mandatory? Yes
3)Is HTML5 Doctype case-sensitive? No
4)HTML5 doctype lang? You can use it in html tag example: <html lang="en-US">
5)HTML5 utf-8 encoding meta character set tag? <meta charset="utf-8">
6)How to validate HTML5 code? visit: https://validator.w3.org/
This is not an AI-generated article but is demonstrated by a human.
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