Link schemes that undermine Google’s search results

(written by Lawrence Krubner, however indented passages are often quotes)

My own experience is that Google has been getting worse lately

The web is big. Like more than a trillion pages big. When a searcher types a couple of words into the search box, Google has to be able to sort through all the pages on the web and show the searcher the ones that are the most relevant to the search, as well as the most useful. That’s a tough challenge. Google uses hundreds of signals to figure this out in an automated way. Historically, the link graph has factored fairly heavily into these relevance and value algorithms.

Google was launched on a foundation of PageRank: the idea that people link to things they like and find valuable, so a page with a lot of links to it is probably more useful than a page without very many links. How people link comes into play too. If a bunch of links to a page use the anchor text “watch the latest episode of Glee online”, then it’s reasonable to assume that the page being linked to has a video of the TV show Glee. (Note: Google has evolved well beyond this simplistic explanation as the web itself has evolved.)

Over time, as site owners realized how valuable it was to rank well in Google search results, some began hatching “link schemes”. Rather than just hope people find our content valuable enough to link to and raise awareness of the content through traditional marketing techniques, how about we just make a deal and agree to link to each other? We both get links with the anchor text of queries we want to rank for and everyone’s happy!

Everyone, that is, except Google. And searchers. Because these types of back room deals break the PageRank algorithm, which was based on a link equating to someone finding the content valuable. With a link exchange, the link simply equates to a deal being made. Less useful results could rise to the top, causing the search results to be of lower quality.

Hence, the Google webmaster guidelines, which at their core say this: our algorithms are meant to surface the best possible results to searchers. If you try to manipulate those algorithms, we might lower your site’s rankings or take your site out of our index entirely.

Matt Cutts manages a very large team dedicated to finding violations to the guidelines and then refining the algorithms to catch them in a wide swath as well as manually remove sites or lower their rankings.