In 2007, U.S. advertisers spent US $24.6 billion on search engine marketing. In Q2 2015, Google (73.7%) and the Yahoo/Bing (26.3%) partnership accounted for almost 100% of U.S. search engine spend. As of 2006, SEM was growing much faster than traditional advertising and even other channels of online marketing. Managing search campaigns is either done directly with the SEM vendor or through an SEM tool provider. It may also be self-serve or through an advertising agency. As of October 2016, Google leads the global search engine market with a market share of 89.3%. Bing comes second with a market share of 4.36%, Yahoo comes third with a market share of 3.3%, and Chinese search engine Baidu is fourth globally with a share of about 0.68%.
PPC (paid search marketing): PPC (pay per click) advertising involves paying to have search engines display your website offer in or alongside search results. For example, Google's Adwords program will display your ad at the top or right side of the search results page (placement depends on many factors including keywords and quality of ad). Google will also feed your ads to websites running its Adsense program. There are other types of PPC marketing, such as Facebook Ads. In PPC advertising, you pay each time someone clicks on your offer. Paid search differs from organize search in that you're paying to have your website or offer displayed higher in search results.
PPC gives you the ability to fix your daily budget depending on how much you’re willing to spend. And since you can start off with a small amount, you don’t have to put a heavy investment at stake before testing the waters. Once you know a certain campaign is giving you a good return on investment, you can ramp up your budget and increase your ad spendings without worrying about incurring losses.