PageRank (PR) is an algorithm used by Google Search to rank websites in their search engine results.
In our case, it is the algorithm to rank the nodes in a given graph.
What is idea behind it?
In short, first taking random walk on the network.
Then, increment the points of each node.
then find the node with the highest points.
Simple !!!
Here, on the top notch, nodes represent the websites
We have two methods for this...
1. Random Walking Method:- Crawlers take random walk on www(world wide web) network and rank the website.
Again in our case, we take randomly a node and finds a (edge) outlink (in reality a hyperlink) and performs a random walk.
2. Points Distribution Method:- Here the concept start from the 'Directed graph' having directed edges.
Real world example:- Email Communication System
That's the idea how ranking works over the web...