Basically, if you want your online business to be successful, it's a good idea to optimize your site on a regular basis to make sure it's got a good position in the Web's top search engines.
Now, what in the world is this SEO?
Thankfully, most of us here, know what it is, but for those who came in late… SEO stands for search-engine-optimization. Now in technical terminology, search engine optimization (SEO) is the process of improving the volume and quality of traffic to a web site from search engines via "natural" ("organic" or "algorithmic") search results. (Thanks wiki !)