Check out example codes for "how to make a yourbue icon in html". It will help you in understanding the concepts better.

Code Example 1

<!DOCTYPE html>
<html>
<head>
<title>Font Awesome Icons</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
</head>
<body>

<h1>fa fa-youtube-play</h1>

<i class="fa fa-youtube-play"></i>
<i class="fa fa-youtube-play" style="font-size:24px"></i>
<i class="fa fa-youtube-play" style="font-size:36px"></i>
<i class="fa fa-youtube-play" style="font-size:48px;color:red"></i>
<br>

<p>Used on a button:</p>
<button style="font-size:24px">Button <i class="fa fa-youtube-play"></i></button>

<p>Unicode:</p>
<i style="font-size:24px" class="fa">&#xf16a;</i>

</body>
</html>

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