Search Engine Marketing
In general, "Search Engine Marketing" refers to paid search marketing, a system in which companies pay Google to display their advertisements in search results which differs from Search Engine Optimization in that SEO is primarily focused on how you rank in unpaid search results.
Search Engine Marketing is the most targeted and effective form of digital advertising by allowing you to put your brand in front of customers who are already actively looking for your products or services on Google, Bing, YouTube or other search engines.
Google AdWords ( also known as pay per click ) is a google-run platform that allows companies to advertise their website in search results when a user searches for a specific keyword. Google AdWords and Search Engine Marketing (SEM) campaigns offer an additional option to SEO in driving high quality Search traffic to a website within a short period of time.
Google AdWords offers a targeted approach to advertising, because you can target specific keywords, interests and devices. To build your list of keywords, it is recommended that you brainstorm, search for similar or competitive brands, talk to customers about what they are looking for and find related keywords using Google Keyword Planner or more sophisticated tools like SpyFu.
Adwords ads appear at the top and bottom of Google's Search Results and under certain conditions you can get your ads positioned at the top. With SEO, on the other hand, you need to work much harder to get one of the top positions in organic search results.
Adwords is more immediate than SEO, because you can create advertising campaigns almost instantly and start getting targeted traffic while SEO requires much more time (especially for new websites) to get good rankings and traffic. Although you should be wary of companies that promise immediate SEO search engine rankings, using paid products such as Google AdWords is the exception to the rule.