SEO has become a familiar acronym. Most people know that it means search engine optimization. But do you really know what it entails? This video provides a clear explanation or search engine optimization:

If you prefer to read, below is a great article by Search Engine Land, a stellar resource for all things SEO.

http://searchengineland.com/guide/what-is-seo

Early on when there were fewer people online, many of the people who used Google, searched for search engine optimization, as pictured in the graph below by Google Trends. People wanted to know how to optimize their webpages so that they would show up high in the search results pages, or SERPs.

Today there are relatively so many more users of the internet, and the interest for search engine optimization over time has declined. People search for other things. Instead of optimizing, there seems to be a trending increase in search for how to pay for traffic. For example, as displayed in this trend, there is an increase in the search term Google Adwords over the same time period: