I noticed many web sites use
<h1><a href="/subdir/somepage/">bla bla</a></h1>
in the page example.com/subdir/somepage/
Why do they do that? SEO? Compliance to some standard I don't know? Does it really help users in any way?
EDIT: after many of the answers obviously misunderstood me. I'm not talking about a link to the homepage of the site. I'm talking about a question page in SO using the question's text in H2 element (see that above?) to link to the same page.