Google has always been criticized for how its algorithm works -- What gets moved to the top of your search results and what gets buried? -- but the heat seems to have been turned up in the past couple of months. With content farms pushing out more and more articles built around high-traffic search terms and web developers and writers growing more SEO savvy, how can Google highlight the best of the best? The search giant is taking a second hit from Facebook, which argues that web users are more interested in what a few of their friends recommend than what an algorithm suggests or thousands of strangers find fascinating. With co-founder Larry Page getting ready to move back into the big seat as CEO, Google has continued to tweak its algorithm, teaching it to ignore as much webspam as possible.

As we've increased both our size and freshness in recent months, we've naturally indexed a lot of good content and some spam as well. To respond to that challenge, we recently launched a redesigned document-level classifier that makes it harder for spammy on-page content to rank highly. The new classifier is better at detecting spam on individual web pages, e.g., repeated spammy words--the sort of phrases you tend to see in junky, automated, self-promoting blog comments. We've also radically improved our ability to detect hacked sites, which were a major source of spam in 2010. And we're evaluating multiple changes that should help drive spam levels even lower, including one change that primarily affects sites that copy others' content and sites with low levels of original content. We'll continue to explore ways to reduce spam, including new ways for users to give more explicit feedback about spammy and low-quality sites.

As "pure webspam" has decreased over time, attention has shifted instead to "content farms," which are sites with shallow or low-quality content. In 2010, we launched two major algorithmic changes focused on low-quality sites. Nonetheless, we hear the feedback from the web loud and clear: people are asking for even stronger action on content farms and sites that consist primarily of spammy or low-quality content. We take pride in Google search and strive to make each and every search perfect. The fact is that we're not perfect, and combined with users' skyrocketing expectations of Google, these imperfections get magnified in perception. However, we can and should do better.

Read the full story at the Official Google Blog.

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