As anyone who has ever worked in a web-based business can confirm, having a good ranking in search results is of critical importance to the success of most online businesses.
And, since Google is the most-used search engine by a ridiculously huge margin, you need to show up in Google search results in order to be noticed on the web.
There are two ways to achieve that: you can put a lot of effort (and money) into building your website's strength organically, slowly creeping up the rankings withing Google's results, or you can simply pay Google to have your content show up on top of regular search results. Search advertising is Google's primary source of revenue and it's a billion dollar business.
According to a ranking published by Ad Age based on AdGooroo data, Amazon alone spent almost $158 million on Google search advertising in the U.S. in 2013, making the online retailer the biggest spender on Google search ads by far. That's why Amazon keeps popping up in your search results and that's one aspect of Amazon's aggressive growth strategy. Other companies in the Top 10 include travel portals Priceline and Expedia as well as retail giants Walmart and Sears.
This charts shows the 10 biggest spenders on Google search advertising in the United States.
You will find more statistics at Statista