The target, rel, media, hreflang, and type attributes must be omitted if the href attribute is not present.

<!-- Link to an external website. -->
<a href="https://www.example.com">Example website</a>
<!-- Link to an internal website in same directory. -->
<a href="home.html">Home</a>
<!-- Download link (5 only). Value of download attribute is used as pre-filled file name in Save dialog.
 If no value is specified for the download the name of the resource will be used.-->
<a href="filename_on_server.pdf" download="meaningful_filename.pdf">Download your pdf</a>
<!-- Open a link in the window specified by the attribute TARGET. -->
<a href="https://www.example.com" target="_blank">Open example website in new window</a>
<!-- Include an IMG element as a part of the link. -->
<a href="https://www.example.com"><img src="/bullet.png">A link with an image</a>
<!-- Link to an anchor on the same page. -->
<a href="#top">Go to top</a>
<!-- Define an anchor. -->
<a id="top"></a>
<!-- Invoke a JavaScript function (Not recommended) -->
<a href="javascript:alert('Link clicked')">Click this link</a>
<!-- Links to a document and uses the rel attribute to specify the relationship to the linked document. -->
<a href="https://www.example.com/help" rel="help">Link to help</a>
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