I read an article the other day that took great pains to illustrate how search engine optimization (SEO) and search engine marketing (SEM) were different. While they both offer different functions, SEO is a subset of SEM. To go out of the way to say they are different is like saying that filling cavities is different from performing dentistry. It is different, but filling cavities is also function of dentistry.

Several years ago when the term "Search engine optimization" was coined, I had my reservations, only because I thought it represented only a limited portion of what many "SEO" companies did. Optimization was one, or for many even the primary function, but not the complete picture. Now a new term is blazing it's way to the forefront, that is "search engine marketing". While again, it represents a portion of what many companies do, I still believe it is still a too narrow representation of the whole.

I've argued for many years that SEO/SEM companies should more rightfully be called "Internet marketing" or "web site marketing" companies. I'm not trying to start a new trend here, but I do think it is important to have some stronger, more accurately defining terms.

Here is a short list of common terms with my version of their definitions and in their hierarchical structure.

Online (or Web Site) Marketing: I think a case can be made that online marketing and website marketing are two different functions, but only slightly. However with the advent of pay-per-call it will be entirely possible to market your online without even having a website. Not sure if that would be advantageous or not, but possible. I place a distinction here between online marketing and search engine marketing because the functions of online marketing , while including search engine marketing, may bypass the search engines altogether.

Examples: email marketing, link buying, renting or exchanging (when done for exposure, not search engine relevance), online ad placement, website design, usability, conversions, etc.

> Search Engine Marketing: SEM is the primary subset of online marketing and focuses its marketing efforts primarily to gain additional web-site exposure via the search engines.

Examples: SEO, Pay-per-click, press release distribution, link building (all forms), keyword research, traffic analysis, etc.

> > Search Engine Optimization: SEO is the act of manipulating a website's on and off-page factors causing the search engines to recognize the site as relevant for specific keyword phrases. The primary function of search engine optimization is get a website ranked, drawing new traffic to the website. What happens once they get there is, by the strictest definition (and one employed by most "SEO" companies) is not under the purview of the SEO company. Usability and conversions are both functions higher up the chain.

Examples: code and text optimization, keyword research, link building, ranking reports, etc.

Many of the jobs that need to be performed can cross each into other categories. For example, keyword research is the function of SEO and SEM, same with link building. It is important, however, to recognize the distinctions in each of these categories. While everything an SEO does is considered a function of "online marketing", if you hire an SEO or purchase an SEO only service, don't expect to receive search engine marketing or online marketing service with that. And if you do want those services included, be ready to pay substantially more for the service.

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