Search Engine Optimization is the process of getting traffic from the “free,” “organic,” “editorial” or “natural” listings on search engines. All major search engines such as Google, Yahoo and Bing have such results, where web pages and other content such as videos or local listings are shown and ranked based on what the search engine considers most relevant to users. Payment isn’t involved, as it is with paid search ads.
Now, why should it affect you? Well, if you are a site owner, or run a business that uses the internet as a medium of relaying your products or services, then a good search result ranking will give you a fighting chance against your competitors, and rake in the joys of return on your investments.