Check out example codes for "doctype html tag". It will help you in understanding the concepts better.

Code Example 1

<!DOCTYPE html>
This tag shows that it is running HTML5

Code Example 2

<!DOCTYPE html>

Code Example 3

<!DOCTYPE html>

<html>

<head>

<title>Title of the document</title>

</head>


<body>

The content of the document......

</body>


</html>

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