PR is an important measurement on the world wide web which is used to give an indication of the value and importance of a page and website. It is gauged on a percentage with the higher values being the better page rank. It is often logarithmically rescaled by Google and was named after Google’s Larry Page, when it was the first algorithm used in their search engine when they started the company. It takes into account link lists and domains and then arranges them according to their value. As such a domain such as USA.gov or CNN.com have very high value and will rank higher in the search than other pages of lower value.

The algorithm itself is done on probability distribution which is taken from the starting point that any person who clicks randomly will land on a random page. That probability will vary between 1 and 0 and the exact number will then be multiplied by 100 and this leads to what we know as PR or Page Rank. A better way of looking at it is to examine the number of outgoing and incoming links from and to a web page. There is a reciprocal of the total amount of sites and in the beginning the PR was that reciprocal value for all of the other pages apart from the one whose PR is then to be found subtracted out of unity.

The basic concept behind PR is probability distribution. A user who randomly clicks at results will eventually cease to after a number of searches. This is known as a dampening factor and has now become a part of the calculation for page rank.

Lastly, there is site speed, which many people don’t realize also affects the ranks. Time taken for pages to load is weighed up by the search engine and faster sites will fare better than slower ones.

Alex is a marketing and SEO expert. He blogs regularly about all things SEO and maintains a blog on freelancing for the Bedouin Group .