Open up Google and search for the term ‘click here’; the top result will be the webpage to download Adobe Reader. Why? The phrase ‘click here’ appears nowhere on that page, nor does it have any relevance whatsoever for the content. However, millions of pages link to the Adobe site so their users can download the reader, and many of them use that anchor text.
What is anchor text?
Anchor text is just a fancy name for the underlined text that makes up a link; it should describe what the link is about. Consider this blog post about why pagerank doesn’t matter. Without even clicking the link, someone reading this page would be able to make a pretty good guess what the linked content is about!
This leads to a better user experience, because the more informative link makes it easier for the users to find exactly what they’re looking for. By contrast, suppose the same link had the text ‘read this article’; not very informative, is it?
How search engines use anchor text
Search engines use anchor text the same way as human readers: to tell then what’s on the other side of a link. Unlike humans, they can’t tell if the page is full of useful, relevant information or not (although they’re getting better), so they rely on other pages to vote on what the page is about. In the case of the Adobe page mentioned earlier, millions of websites have told Google that the Adobe page is about “click here”, so Google puts it at the top of the SERPs for that search term.
Any (dofollow) link is helpful for increasing pagerank, but sites that have backlinks using relevant text will rank well for the terms being used, which helps users to quickly locate what they’re looking for.
Good and bad anchor text
Good anchor text for a link is text that accurately describes the page the link is pointing to. Superlatives like “the best site every!!!” are not particularly useful. Additionally, to be useful to the search engines it is helpful if the anchor text is a term that people will actually search for when looking for the associated content; the name of a blog, for example, might accurately describe the link, but unless the blog title contains keywords it’s unlikely that users will be searching for it.
A mistake many novices make is linking to sites using the name of the site owner as the keyword; that may be great for vanity searches, but it doesn’t do much for people looking for posts on a particular topic.