The heart of our software is PageRankâ¢ (www.google.com/technology) The seven words quoted above say it all. There have been many additions to Google's algorithm since Sergey Brin and Lawrence Page invented the concept of PageRank, but PageRank is still the trademarked backbone of Google's algorithm. At the same time we must assume that other search engines have implemented their own versions of "pagerank" - such as Web Rank and TrustRank This means that anyone who wants to learn about search engine optimisation must first learn the theory behind PageRank The idea behind this site is to use a brightly coloured spreadsheet for watching how PageRank distributes throughout a site. Adding and deleting links is as easy as entering 1 and 0 in the spreadsheet I hope this will give a more visual idea of PageRank - and at the same time answer time-old questions - such as "does PageRank leak exist?" and "which linking structure is better?" If you have Microsoft ExcelÂ© you can get the spreadsheet and tune all the parameters. If you do not have Excel installed on your computer you can still see the examples, but will not be able to play around with different values Please note that all through this site, the word PageRank refers to the **real** PageRank - and not to the logarithmic PR display from the Google Toolbar.