Google launched an algorithm update called Panda in 2011 aimed at low-quality content sites. Panda targeted sites with shallow, duplicate, redundant, or poorly written content and those with an excessive amount of ads. It impacted 11.8% of search results initially. The update particularly hurt Demand Media's eHow site, which lost 42% of search visibility and 28% of revenue from Google. To protect against future Panda updates, the document recommends diversifying traffic sources beyond Google and focusing on delivering high-quality, original content to users.