The IANA registry contains a official link relation type of "related"
related: Identifies a related resource.
https://www.iana.org/assignments/link-relations/link-relations.xhtml
I have also read the referenced RFC4287.
The value "related" signifies that the IRI in the value of the href attribute identifies a resource related to the resource described by the containing element. For example, the feed for a site that discusses the performance of the search engine at "http://search.example.com" might contain, as a child of atom:feed:
<link rel="related" href="http://search.example.com/"/>
An identical link might appear as a child of any atom:entry whose content contains a discussion of that same search engine.
But that only seemed more confusing to me. Aren't all links related? After all rel = relation.
Can anyone try to clarify this and give valid use cases for rel="related"? Is it just a catch all relation type?