In 2007, U.S. advertisers spent US $24.6 billion on search engine marketing.[3] In Q2 2015, Google (73.7%) and the Yahoo/Bing (26.3%) partnership accounted for almost 100% of U.S. search engine spend.[4] As of 2006, SEM was growing much faster than traditional advertising and even other channels of online marketing.[5] 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%.[6]

For example, to implement PPC using Google AdWords, you'll bid against other companies in your industry to appear at the top of Google's search results for keywords associated with your business. Depending on the competitiveness of the keyword, this can be reasonably affordable, or extremely expensive, which is why it's a good idea to focus building your organic reach, too.
Search engine marketing’s greatest strength is that it offers advertisers the opportunity to put their ads in front of motivated customers who are ready to buy at the precise moment they’re ready to make a purchase. No other advertising medium can do this, which is why search engine marketing is so effective and such an amazingly powerful way to grow your business.
Because it appeared quickly, social media has developed a reputation by some for being a passing marketing interest, and therefore, an unprofitable one. The statistics, however, illustrate a different picture. According to Hubspot, 92% of marketers in 2014 claimed that social media marketing was important for their business, with 80% indicating their efforts increased traffic to their websites. And according to Social Media Examiner, 97% of marketers are currently participating in social media—but 85% of participants aren’t sure what social media tools are the best to use.
Inbound marketing refers to a marketing methodology wherein you attract, engage, and delight customers at every stage of the buyer's journey. You can use every digital marketing tactic listed above, throughout an inbound marketing strategy, to create a customer experience that works with the customer, not against them. Here are some classic examples of inbound marketing versus traditional marketing: 
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