Whats purpose of RSS fees link in header?
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Most of the news/blogs websites include RSS feeds link in their header. For example:

    <link rel="alternate" type="application/rss+xml" title="Example Feed" href="http://example.com/feed/" />

I want to know what is the practical use of adding above? Is it to tell the browser that the website has RSS feeds? In past Firefox has the button in the address bar, but now they have remove it. Also if some user want to subscribe the RSS, he needs to enter the feeds url directly. So where it is being used? Thanks