Part of what my day job consists of:
You have most likely heard of the term “keyword optimization.” If you haven’t, the gist of the concept is to optimize the content of a webpage to maximize the probability of a user finding your site on Google, Yahoo!, or some other search engine. Seems straightforward enough, right? Keyword optimization, nevertheless, becomes difficult when choosing which keyword(s) to optimize for. A common strategy is to choose “obvious” search terms and optimize the content for this keyword — which sometimes really means: use that keyword as often as possible (remember, there are diminishing returns to keyword usage!). What many people don’t realize is that such a strategy can hurt, rather than help, your search engine results.
Suppose that you are a dentist with an infosite dedicated to dental implants. You want to draw traffic to your website by pushing it to the top of the Google search page. An easy method of doing this, one might think, is to use the term “dental implants” as often as possible. The problem with this is that there are thousands of dental implant providers out there, all of which might be using the same exact SEO approach as you. In other words, you are competing with thousands of other websites which are optimizing for the same exact search term. You might, instead, refine your optimization by adding your city name: e.g. “Dental implants in Albuquerque, NM.” You are now dipping your big toe into the world of long-tail SEO optimization.