Google's search engine marketing is one of the western world's marketing leaders, while its search engine marketing is its biggest source of profit. Google's search engine providers are clearly ahead of the Yahoo and Bing network. The display of unknown search results is free, while advertisers are willing to pay for each click of the ad in the sponsored search results.
In 1998, two graduate students at Stanford University, Larry Page and Sergey Brin, developed "Backrub", a search engine that relied on a mathematical algorithm to rate the prominence of web pages. The number calculated by the algorithm, PageRank, is a function of the quantity and strength of inbound links. PageRank estimates the likelihood that a given page will be reached by a web user who randomly surfs the web, and follows links from one page to another. In effect, this means that some links are stronger than others, as a higher PageRank page is more likely to be reached by the random web surfer.
One of the things that can slow-bleed the traffic from your site is the quality (or lack thereof) of the content you publish on your site. Previous Google updates like Panda have already been released specifically to deal with the issue of low-quality content on websites. Long story short: Panda intended to stop sites with bad content from appearing in the search results.