One of the things that Google introduced when it took the web by storm was the PR system.  PageRank (PR) is Google's new-generation system for sorting webpages based on their importance.

A page's PR is ranked on a scale of one to ten and takes into account two main factors: the relevance and content of the page, and the number and quality of links leading to it from other websites. When a user searches for a website, Google first pulls all the relevant pages from its database, and then sorts them by PR. If two pages have the same relevance, the page with the higher PR will be given priority in the search listings.

In general, the more inbound links you have from high-PR, relevant pages, the higher your PR will be. It is important to note that the pages that link to you should have similarly-themed content; for example: McDonald's linking to Microsoft won't benefit Microsoft a lot because their content is completely different.

Another point to note is that PR is believed to be calculated on a logarithmic scale (I use the word "believed" because nobody except Google knows for sure), which basically means that it is much harder to go from PR 6 to PR 7 than PR 2 to PR 3.

To illustrate, consider the following sample data:

Displayed PageRank	Actual Page Importance
3	10
4	100
5	1,000
6	10,000
7	100,000

That data is for demonstrational purposes only, but if we assume that it's true you can see that the values increase by tenfold each level. That means that is is ten times harder to climb to the next PR.

This also means that 1 link from a PR 8 page can be much more beneficial than a few hundred links from PR 1 pages. Fortunately, this system effectively renders link farms (webpages with lots and lots of links for the purposes of artificially inflating PR) practically useless, as these pages often have a very low PR and therefore are not benefiting the linked site.

The last question that a lot of people have is "Wow! Now I know what it is, but how do I check my PageRank?"

Well, the easiest way and most reliable way to check your page's rank is to download the Google toolbar. You can get it by clicking on this link.

I hope that after reading this article you now understand the underlying principles of PageRank.