Check out example codes for "meta tags". It will help you in understanding the concepts better.

Code Example 1

<head>
  <meta charset="UTF-8">
  <meta name="description" content="Free Web tutorials">
  <meta name="keywords" content="HTML, CSS, JavaScript">
  <meta name="author" content="John Doe">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
</head>

Code Example 2

<meta name="viewport" content="width=device-width, initial-scale=1.0">

Code Example 3

<meta http-equiv="refresh" content="30">

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