the five of the terms that you likely hear on a daily basis, but may not fully understand.

* Algorithm -- Algorithm is really just a fancy word for "formula."

Whenever one of the search engines ranks your site, it uses this formula to figure out how relevant your site is for people doing the searching.

So the search engine will look at your site's content, your keywords, your inbound links, and so on, and then calculate your position on the search results page.

The more relevant the search engines determine your site to be using the formula, the higher they'll place you on the results page.

Algorithms are top secret, and they're frequently being "tweaked," so it's possible to earn a high ranking, only to suddenly lose it for no apparent reason!

* Page Rank -- Page Rank is calculated by Google, and is a measure of how they value your site.

Page Rank is measured on a scale of 0 to 10, with the average being 3 or 4. To calculate it, Google looks at factors like your content, and the number of one-way links pointing to your site.

The links are an important factor in the calculation. The more other sites consider you to be a good and relevant resource (and therefore link to you), the more Google will think so, too.

To see your (and other sites') page rank, you need to download the Google Toolbar,

* Link popularity -- Most people know what links are, but did you know that some kinds of links can help your search engine placement, while others might actually hurt it?

Take "reciprocal" links, for instance...

If you link to someone's site, and they link back to you, that's considered a reciprocal link... and the search engines do NOT like them.

That's because, at one time, the search engines just looked at the number of sites that linked to you, assuming the more links you had, the better your site was.

Of course, it didn't take people long to start getting as many sites as possible to link to them, no matter whether the sites were relevant or not, just to improve their ranking...

... and the search engines figured out just as quickly that this was going on.

Nowadays, the best link is a one-way link from a relevant website to you.

* Keyword Phrase -- Where we used to talk about keywords, more and more, we're talking about keyword phrases.

This is because, at this stage in the Internet's evolution, so MANY people have already targeted most single words, that there's not much value in going after them anymore.

So when people look for keywords to target now, they look for keyword phrases, which contain 2, 3, 4 (or more) words.

The value of using keyphrases is that you can be much more specific about what your site (or individual pages within the site) are about.

* Site structure -- This refers to the way your website is organized, how the pages are linked together, and how your menu works (some people refer to site structure as the "information architecture").

The structure of your site not only helps your visitors move more freely through the pages, and find the information they're looking for more quickly, it can also help improve your rankings in the search engines.

That's because a well structured site has all of the relevant pages carefully linked together, and the search engines love relevant and related content.

By understanding these five basic concepts, and how they effect your search results, you'll be in a much better position to get start off on the right foot with your optimization efforts.