The name PageRank is a trademark of Google, and the process of assigning the PageRank has been patented. But the patent is assigned to Stanford University and not to Google. Google only has the private license rights on the patent from the Stanford University. The university got 1.8 million shares of Google for the use of the patent.
The PageRank is a link analysis algorithm, which is named after Larry Page and is used by Google internet search engines. The Google PageRank is a numeric value which is used to indicate the importance of a page on the internet. The Google believes that, one page linked to another page effectively votes for the other page. More the number of votes for the page, higher are the importance of the page. And in this way the importance of the site which casts the vote, will decide how important the particular vote is. In this way Google calculates the votes cast for the page and decides its importance. Also the importance of the votes cast is taken into consideration during the calculation of the PageRank.
It is a way for Google to evaluate and decide the importance of a working page. This is very important as this is one of the factors that determine the PageRank in search results. Remember that it is not the only factor that Google uses but this is the one of the important one. Also note that all the links are not counted by Google. It filters links from what is called as link farm. Remember some links can cause a site to be punished by Google. They know that it is not possible for webmaster to control which site links to his site. However they can control which site they link to. Due to this you must be careful, which web sites you link to.
