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

Code Example 1

<link rel="icon" type="image/png" href="/favicon.png"/>
<link rel="icon" type="image/png" href="https://example.com/favicon.png"/>

Code Example 2

<link rel="shortcut icon" type="image/png" href="http://example.com/favicon.png"/>

Code Example 3

<link rel="icon" href="image.jpg" type="image/jpg">

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