Presenting the PageRank algorithm
As a practical example, let’s look at the PageRank algorithm, which is used by Google to rank the search results of a user query. It generates a number that quantifies the importance of search results in the context of the query the user has executed. This was designed by two Ph.D. students, Larry Page and Sergey Brin, at Stanford in the late 1990s, who also went on to start Google. The PageRank algorithm was named after Larry Page.
Let’s first formally define the problem for which PageRank was initially designed.
Problem definition
Whenever a user enters a query on a search engine on the web, it typically results in a large number of results. To make the results useful for the end user, it is important to rank the web pages using some criteria. The results that are displayed use this ranking to summarize the results for the user and are dependent on the criteria defined by the underlying algorithm being used.
