Google Ads (formerly Google Adwords) is the search provider most commonly used for this strategy. With this tactic, brands conduct keyword research and create campaigns that target the best keywords for their industry, products, or services. When users search for those keywords, they see the custom ads at the top or bottom of SERPs. The brand is charged each time a user clicks on the ad.
Today, however, SEM is used to refer exclusively to paid search. According to Search Engine Land, Search Engine Marketing is “the process of gaining website traffic by purchasing ads on search engines.” Search Engine Optimization, on the other hand, is defined as “the process of getting traffic from free, organic, editorial or natural search results.”
Inclusion in Google's search results is free and easy; you don't even need to submit your site to Google. Google is a fully automated search engine that uses web crawlers to explore the web constantly, looking for sites to add to our index. In fact, the vast majority of sites listed in our results aren't manually submitted for inclusion, but found and added automatically when we crawl the web. Learn how Google discovers, crawls, and serves web pages.3
Optimization techniques are highly tuned to the dominant search engines in the target market. The search engines' market shares vary from market to market, as does competition. In 2003, Danny Sullivan stated that Google represented about 75% of all searches. In markets outside the United States, Google's share is often larger, and Google remains the dominant search engine worldwide as of 2007. As of 2006, Google had an 85–90% market share in Germany. While there were hundreds of SEO firms in the US at that time, there were only about five in Germany. As of June 2008, the market share of Google in the UK was close to 90% according to Hitwise. That market share is achieved in a number of countries.
Optimizing a website may involve editing its content, adding content, and modifying HTML and associated coding to both increase its relevance to specific keywords and remove barriers to the indexing activities of search engines like Google ,Yahoo etc. Promoting a site to increase the number of backlinks, or inbound links, is another SEO tactic. By May 2015, mobile search had surpassed desktop search.