Even more interesting is the fact that the words "Click Here" are nowhere on the page. It would be silly to use "Click Here" as keywords because it is not a normal search term, and Adobe did not even include them anywhere on the page text, title, description, or in any metatags at all. So why does Google rank Adobe's download page number one on that term?

The answer is external links. As a convenience to customers and site visitors, just about every web site that has a PDF file available also has a link to Adobe for the Acrobat download. And almost invariably, the link text is something like, "If you need Acrobat Reader, click here."

The Adobe example illustrates a key point about links: The search engines use anchor text as a huge hint as to what the target web page is really about. Anchor text, for those who need to know, is the visible link text that you click on in the browser when the page is rendered.

In some ways that makes our lives more difficult because we cannot control how others link to us, much less whether they link to us. There are some ways around this that I'll touch cover in the next installment. But first a word about Page Rank.

Page Rank values range from 0 to 10 (which is an eleven point scale, oddly enough). The actual components of Google's Page Rank calculation are yet another closely guarded secret, but it doesn't take a genius to see that the number of external links to your page is a huge part of it.

The importance of Page Rank is sometimes overblown since search engines must by definition care more about a page's relevance to search queries. However, Page Rank is definitely one of the factors that will push your page higher in the crowd of equally relevant pages returned as query results. If you have virtually no competitors for your primary keywords, don't worry about Page Rank. The rest of us need to have it on our radar.

There are precious few PR 10 web pages and at the time I'm writing this, Adobe's Acrobat download page does indeed have that coveted PR 10 ranking. It certainly got the bulk of its rank because so many sites provide unreciprocated links to it. Another factor in Page Rank appears to be age: All things being equal, sites that have been around longer tend to have higher Page Rank values.

A hint to those still awake: The age factor as well as the Google sandbox described in part 1 of this series are both powerful arguments for getting web sites up and spidered as soon as possible, even if only as prototypes or proof-of-concepts.

If you were to survey tens of thousands of web sites, I believe you'd find that the most successful private, non-corporate web sites have a PR of 6. There are very, very few PR 7 sites, and if you've managed to achieve a PR 4 or 5 without professional SEO help, you've done pretty well.

Now we come to the slightly depressing part: One of the best ways to improve your page rank (and therefore improving the tendency to show up higher in search results) is to get an unreciprocated link to your page from a page with a higher page rank. If the Acrobat download page linked to my site, I'd be sitting pretty.

But alas, such links are very difficult to come by. Even worse, the one thing we can easily offer is a return link, but such reciprocal links have dubious value. I have anecdotal evidence that their value is rapidly declining and they are worth far less now than they were just one month ago when I wrote those words.

Here's another tip: Reciprocal links to sites that have nothing to do with your web site in terms of content are a total waste of time. If you have a site about wedding gowns and you exchange links with a gambling site, in my opinion you've achieved nothing.

In fact, I predict that if Google finds many reciprocal links with unrelated sites on your web page, you will actually be punished in terms of your page's ranking.

The spider likes it when you link to things that provide value to your visitors. And the spider gets angry when you trade worthless links solely for the purpose of fooling it into thinking your site is wildly popular. I predict spidey will bite you, if not today then tomorrow.