THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
PageRank
PageRank is one of the foundational algorithm's of Google's indexing process: ranking every web page on the internet by the number and quality of links.
It is described on Wikipedia, though what is not discussed is how PageRank-style algorithms can be implemented with MapReduce. The answer is: iteratively. Some aspects of this have been covered by Paolo Castagna talking about Graphs.