Is there any difference between pagerank and Topic Sensitive Pagerank? To answer this question we need to first analyse the Google's Pagerank (PR) system.

The term Pagerank though now commonly refers to the position of a page in any search engine it is originally a trademarked technology of Google. It is a numerical ranking system to assess the relative importance of web pages created by the Google founders Larry Page and Sergey Brin at Stanford University in California .

To quote their own words, the concept of pagerank calculates the, "uniquely democratic nature of the web by using its vast link structure as an indicator of an individual page's value."

Pagerank system is based on the incoming and outgoing links from all those millions and millions of web pages that constitute the Internet. A superficial simple understanding would be something like this, if a web page A links to web page, then page A is voting for the importance of page B. The logic behind it is you would like to be associated to a site if and only if you consider a site to be of some importance to you thus vouching for its importance. Though sounds simple, Google's pagerank is much more complex than that.

With the current pagranking calculation the pagerank remains constant at a single ranking as it uses the calculation that is performed once is totally independent of the search query.

But with the Topic sensitive Pagerank system, only those links that are relevant to the site's content will gain great significance where as leaving the links from irrelevant or less relevant pages in the dark without much recognition. This makes the ranking scheme sensitive to topic.

Topic sensitive pageranking scheme obviously should use precalculated vectors and to do that it should have a prototype to base its calculations which it draws from the Open Directory Project (DMOZ) database. The limitation here is the range or the scope is narrowed down as only limited number of themes would be used for the prototype calculations.

To save time and increase efficiency of processing operation, Topic Sensitive Pagerank scheme will be a pre-computed method. The beauty of this method is that, each page will be scored against multiple topics resulting in many pagerank numbers depending on the total number of themes used in the computation.

A composite number for every topic will be created during the time of search query using all the pre-calculated PR numbers. The pages gain the advantage of many PR numbers depending on how each topic is weighed making the PR number vary from search to search. This way of calculating the pagerank using topic sensitivity factor redeems the webpages from life of death mode of existence.

Topic sensitive pageranking method uses a very complex mathematical formula, that calculates and generates topic vectors offline prior to updates. Typical to Google, no one ever comes to know the parameters of the formula used.

All that could be gathered regarding the formula is that it is heavily based on Open Directory Project (DMOZ) categories. Apparently these categories are free from any bias, the validity of this statements however stands questioned in the scholarly circles.

There are two ways the calculations are performed for every individual query. No one can vouch for the method that Google uses in the tabulation.

The first way employs the following method, all users who search using a particular keyword or particular combination of keywords will see similar results. Uniformity is one of the basic parameters used by this first method.

While the first system seeks to achieve uniformity, the second system promotes plurality. The second method tries to make the results individualized to search engine users by taking into account the individual's prior searches and surfing habits and personalizing the search results to suit the individual's interests. This just as we look at it is complex and it presupposes the use of surfer tracking techniques.

All the incoming links have fixed PR value irrespective of the themes of the pages. For instance, a PR6 page will passes along that value to the receiving page regardless of the theme of the receiving page, be it a page on avionics or be it a page on travel.

Where as in a Topic Sensitive system, the PR value that is passed on would vary within a given range depending on the relevance of the link to the incoming page measured against the various categories employed in the Open Directory Project. As obvious as it should be, the TSPR value fluctuates from one receiving page to the other. For instance the travel page would not receive as much PR from the avionics page, as would a page on tourism.

This method of ranking the pages reflects heavily on reciprocal link exchange. It changes the entire dynamics of the reciprocal link exchange trade, as the value of a page depends heavily on the type of the site under consideration.

In this scenario, reaching the status of an authority site gets ever more difficult a task, as not every link that is exchanged is going to bring worthy results, website owners should get really careful in their selection of exchange links, careful enough to choose links from similar or relevant sites.

Does this topic sensitive pageranking system to the benefit of the webmasters or does it only complicate more the already complicated SEO dreads?

Some of the basic implications of Topic Sensitive pageranking system coming to effect are, firstly it calls for a ever new approach of search engine optimization. New method, new algorithm all mean the SEO professionals have to burn their midnight oil in learning, analyzing, and mastering the skills required to benefit from this new methodology.

With regard to the current pagerank calculation, the basic PR formula is a published secret and the SEO professionals are fairly familiar with the theory behind it and the calculations involved in it. Though the original equation has undergone several modifications, the underlying theory remains constant. Moreover, the single PR number is commonly understood.

The introduction of Topic Sensitive Pagerank will bring in whole new way of looking at search engine optimization. It will certainly complicate the whole business. It is going to demand extra sweat to gain links from theme worthy sites, not link from any site is going to help, such a careless choice may even hinder the benefits flowing into a webpage.

Constant up dating of your site with fresh and relevant content will become even more crucial to entice natural linking.

On the positive note, searches will become even more effective and efficient. Searches can be personalized, as the pagerank gets topic oriented specific to each page.

Now with the information at hand SEO professionals are literally blind folded with regard to Topic Sensitive Pagerank calculations as the parameters that will be used in the calculations are much of a mystery. Such a situation limits even the scope of speculations limiting it to the implication of Topic sensitive pageranking.

Having said that, as far are us we are concerned Google's pagerank mystery is only going to change its shape and is not going to be revealed.