Google: What is the best layman explanation available for Google's Pagerank algorithm?

Once upon a time, there were two tourist guides, let's name them A and B in a beautiful tourist spot. A is well experienced and has a very good knowledge of the tourist places around. He is the most famous tourist guide and everybody loves him as he knows what exactly visitors would enjoy and expect in their fun trip. A has guided too many people that he already knows what will any visitor would expect from him. A is loved by all because he is amazing and understanding about the visitors expectation. B is relatively young and has less experience in the business. B is very enthusiastic but has less knowledge about the visitor expectation and the places they might like to hangout. So B is relatively less popular and people always preferred to hangout with A. Tourist guide A knows what a visitor would look for, by taking into account  of the expectation of the visitor (several parameters). This knowledge set of A makes him amazingly smart and making it almost impossible for tourist guide B to stand a competition. Tourist guide A is Google and his knowledge about places and visitor expectation is the page rank which is more relevant to users as it is used by more people and the tourist spot is the world wide web (Internet). B is other search engines like Bing, Yahoo! who have great potential but not enough of usage statistics.

I will try to give a cool explanation of the pagerank algorithm: Prior to Google, then leading search engines like Yahoo,Altavista etc, searched and ranked pages in an non-increasing order based on the frequency of the occurrence of the particular keywords in the search query. But, Google founders found loopholes the above solution to the all-important internet search problem.For example: [This particular instance gave me a smile] Google founders tried to search the term "Altavista" in Altavista, and were shocked to see that the search engine[i.e altavista] was unable to search itself.This lead them to think of a better ways to address the internet search problem.And here comes the googly - "PageRank Algorithm" . The PageRank algorithm gives equal importance to page citations, in addition to the page itself.Google Founders found out that becoming knowledgeable of the links in a page, has a significant role in search.Abiding by the pagerank algorithm,  every page along with the pages linked by the citations, are given a score.This score is additive in nature. This score is used by google to rank its pages.Thus, the effectiveness of the search is based on the scoring.And, regular web crawling using bot, will give us most appropriate answers in matter of seconds. P.S: I hope my explanation was  simple enough for  any person with non-CS background to understand. Also, If you are interested to learn more about google and how its came into being, I would suggest u read: 1.  The Google Story      http://www.google.co.in/url?sa=t&rct=j&q=the+google+story+ebook&source=web&cd=1&cad=rja&sqi=2&ved=0CCkQFjAA&url=http%3A%2F%2Fyanko.lib.ru%2Fbooks%2Finternet%2Fgoogle_story-l.pdf&ei=FLrVUZegPI-zrAe94ICABA&usg=AFQjCNGVY0B_i55BL8ZhRSBvkBy8HHlhUA&bvm=bv.48705608%2Cd.bmk

If I explain to you how pagerank algorithm works and if Larry Page (one of Google's co founder) explains whom will you trust more? I think Larry Page :P . Why? Because he is more trusted authority on the subject. Google also do something similar. It gives more weight to the link which is coming from more trusted sources. Trusted sources are the one with more number of citations. It is similar to how research paper citations work. More citation to one paper, more trusted it is.