One final tip on page relevancy is the point on having your keywords and phrases in links which point to your site. It's a good idea to have the linking text contain your keywords as Google even says itself in its description of its Pagerank™ technology that it analyzes pages that links come from.
How much keyword laden links matter is anyone's guess. I have however noticed a lot of sites which give the HTML code to visitors who want to exchange links do include keywords in the actual linking area. You should do this too on your links page, say something like "if you want to link to this site, please use the following code". The code would of course have your most important words in the actual link text and your less important words in the accompanying description of your site.
In the above section of the article you've learned what areas Google uses and looks at when looking for a relevant site, but what method does Google use to determine which site is better, the answer is the Pagerank™ system.
Pagerank™ is as the name suggests a ranking system of pages. It works on the basis that if a website ABC.COM has been linked from a website XYZ.COM, abc.com must have some good content and therefore Google will count the link from XYZ.COM as a vote for ABC.COM. You can check your Pagerank™ on Google by downloading the Google toolbar from http://toolbar.google.com.
The Pagerank™ scale goes from 1 to 10 on the Google toolbar and from 1 to 7 beside listings in the Google directory. A less important site is of course a site with a PR of 1 and a very very important site is a site with a PR of 7 or 10, in the directory or toolbar respectively.
The more links or votes a site has the more important it must be and therefore the higher it will rank for search words which it is relevant to, right? WRONG!.
Google does not simply count the number of incoming links a page has, if that was the case every webmaster from Iceland to Vietnam would try and exchange links to every Tom, Dick and Harry website that would let them. In Googles own words:
"Google looks at more than the sheer volume of votes, or links a page receives; it also analyzes the page that casts the vote. Votes cast by pages that are themselves "important" weigh more heavily and help to make other pages "important"."
Hopefully your beginning to get the idea. The idea is to have your page linked to by as many high quality and high pageranked sites as possible. Right? RIGHT and WRONG.
WRONG BECAUSE, you see the Google Pagerank™ system also takes into account the number of links the page that has linked to you has. The reasoning for this is that a page X has a certain amount of voting PR, if your site Y is the only link from that page X, then Google feels confident that page X thinks your page Y is the best link it has and will give you more PR. If however page X has 50 links, page X could think your only the 50th best link. Hence the more links a page has the less of a PR boost your site will get.
RIGHT BECAUSE, linking to a site with a 6+ PR will provide a significant boost to your PR in most cases, but in cases where the site also links with 100 other sites the boost will be almost zero. Likewise if a site has a PR of just 2 but you and only one other site are linked from it, then the PR boost would be more than the site with 100 links and a PR of 6.
It's beginning to come complex isn't it, just wait till you see this formula. It looks scary for non math's people.
First let me explain what the damping factor is. The damping factor is the amount of your PR which you can actually pass on when you vote / link to another site. The damping factor is widely known to be .85, this is a little less then the linking pages own PR.
PR(A) = (1-d) + d(PR(t1)/C(t1) + ... + PR(tn)/C(tn))
In layman's terms PR(A) is the Pagerank™ boost your page A will get after being linked from someone else's site (t1). PR(t1) is the pagerank of the page which links to you and C(t1) is the amount of total links that (t1) has. It is important to know that a pages voting power is only .85 of that pages actual PR and this voting power gets spread out evenly between all sites it links to.
Imagine http://www.akamarketing.com was linked by XYZ.COM's link page which had a PR of 4 and 9 other links, here's how the formula should look like:
PR(AKA) = (1-.85) + .85*(4/10) PR(AKA) = .15 + .85*(.4) PR(AKA) = .15 + .34 PR(AKA) = .49
To sum up my site would get an injection of .49 PR after being linked from a page with a PR of four and 9 other links.
Let's say I was linked from a site with a PR of 8, double the previous example's amount, which had 15 other links, a total of 16 outbound links, my boost would be:
PR(AKA) = (1-.85) +.85*(8/16) PR(AKA) = .15 + .85(.5) PR(AKA) = .15 + .425 PR(AKA) = .575
The above two worked examples show that not only is the PR of the linking page important but what is also important is how many other sites are also linked to from that page.