Check out example codes for "connext html file to css". It will help you in understanding the concepts better.

Code Example 1

<link rel="stylesheet" type="text/css" href="style.css">

Code Example 2

Three ways to add CSS to the body of html:
	1)External CSS
	2)Internal CSS
	3)Inline CSS

1) Externally:  
    Type your css code in a file. Remember you file name.
	Then,
<head>
	<link rel="stylesheet" type="text/css" href="FileName.css" >
</head>

2) Internally:
	Type your cSS in the html file itself. (It is not preffered until
	little CSS code is to be added). This can be done by style tag.
	Example:
	<head>
	<style>
	h1 {
      text-color:red;
      text-size: 0.8em;
    }
    </style>
	</head>

3) Inline:
	This method is not used by developers as it is very lengthy and
	maintaining code becomes difficult.
	Example:
   <h1 style="color:blue;text-align:center;">Header file</h1>

Code Example 3

<!DOCTYPE html>
<html>
<head>

  <link rel="stylesheet" href="styles.css">

</head>
<body>

<h1>This is a heading</h1>
<p>This is a paragraph.</p>

</body>
</html>

Code Example 4

<link rel="stylesheet" href="styles.css">

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