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

Code Example 1

<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
        <title>HTML basics</title>
    </head>
    <body>


    </body>
</html>

Code Example 2

HYPER-TEXT MARKUP LANGUAGE
Is the standardised markup language (a subset of XML) that 
defines the layout of a webpage. 
HTML has no functional properties, other languages such as 
JavaScript must be used in order to manipulate the layout
and perform HTTP requests.
CSS (Cascading Style Sheets) is commonly used to style the
elements in the layout.

Code Example 3

p
<p>
hello world
</p>

Code Example 4

<!DOCTYPE html>
<html lang="pt-br" xml:lang="fr" xmlns="http://www.w3.org/1999/xhtml">
<head>
	<link rel="stylesheet" type="text/css" href="style.css">
	<title>...</title>
</head>
<body>
	...
<script type="text/javascript" src="script.js"></script>
</body>
</html>

Code Example 5

<!DOCTYPE html>
<html><head><title>Page Title</title>
</head><body><h1>This is a Heading</h1><p>This is a paragraph.</p>
</body></html>

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