Search Engine Optimization (SEO) is a very broad field that can be confusing to those just getting their feet wet in Internet publishing and e-commerce. Because of that, the so-called SEO "gurus" typically focus on a small handful of SEO techniques that cover the basics of optimizing a website for good rankings in the search engines.

Keyword density

This is a simple one that most people are familiar with. Getting your keyword density right by repeating a certain word or phrase enough times (but not too many times) in a page or article means the search engines are more likely to give you a good ranking when people search for that keyword or phrase.

Content Placement

Search engines are busy beasts. They have to filter though millions of pages. At the end of the day search engines are just software robots? and software robots and the hardware they run on can be quickly overworked. To protect against this, some search engines may only index a page up to a certain point, so make sure your most important content containing your keywords comes first.

Header Tags

The use of header tags such as h1, h2 and so on is also a good way to get the search engines to take notice of particular keywords in your pages and articles. Most search engines assign weight to keywords according to the level of the header tag used - h1 being the highest and h6 the lowest and so on.

Alt and Title Attributes

A great way to get a few extra instances of your keyword(s) into your page or article is to provide any images with "alt" and "title" attributes containing those keywords.

What's Missing? Site Structure

As noted earlier, the above methods of search engine optimisation are all common to most people getting into Internet publishing. What we want to focus on is an equally important, but often overlooked, aspect of SEO: website structure.

The previous methods of optimizing a website are all aimed at convincing a search engine that a particular page is worthy of a high ranking on its own merits. But as everyone knows, inbound links to a page or website play a big role ? arguably the biggest role - in determining search engine rankings.

For a new website, links from other websites may be somewhat difficult to come by, at least in any large number. Some SEO commentators have suggested that search engines may index every page of a website as though they were all separate websites.

Thus a link from one page to another page in the same website would in this case pass on the same kind of "link juice" that determines search engine rankings as a link from an external site.

This is where site structure comes in.

A website can be structured to make sure that the flow of link juice is building up the pages you most want to get a high ranking for. The home page is a good place to start. Every page of your website is probably linking back to your home page, giving it a nice small boost of link juice to start out with. Additionally, any external sites you do manage to win a link from will most likely link to your home page.

Now that your home page has a nice bit of link juice to play with, you want to make sure that the most important pages of your site are linked to directly from that home page. The further from the home page that another page sits (read: the more clicks it takes to reach a particular page), the less link juice it may end up with.

It used to be popular to build "deep" websites that went down several layers for the sake of effective page management, but with search engines playing such a major role in the economy of a website, "shallow" is now arguably better.