SEO - Search Engine Optimization
Search Engine Optimization, or SEO, is simply the act of making the pages and navigation of your site as friendly to the search engines as possible. You make sure that you take into account all the factors that help tell the search engine what your page is about.
As far as I am concerned, it is about getting targeted traffic to the appropriate pages. It is not about driving sheer numbers to pages that do not serve their needs. In fact, sometimes it is useful to use your knowledge of SEO to reduce your traffic from inappropriate keywords.
I am also not much of a fan of most professional SEOs. There are certainly some good ones out there, but the truth of the matter is that most of them rely on the trick-of-the-day gleened from the various SEO forums to get you quickly and easily to the top for now but they do little to try and secure your long term rankings. Then again, who can blame them, most people aren't going to paythem to slowly build up traffic in a natural manner.
My articles on SEO all concentrate on building a long term, robust site with real content. It might be of use to those that want to build fly-by-night sites, but they are not my target audience.