What is Hadoop
Yahoo hired someone named Doug Cutting who had been working on a clone or a copy of the Google big data architecture and now that’s called Hadoop. And if you google Hadoop you’ll see that it’s now a very popular term and there are many, many, many if you look at the big data ecology there are hundreds of thousands of companies out there that have some kind of footprint in the big data world.
In a big data cluster what Larry Page and Sergey Brin came up with is very pretty simple is they took the data and they sliced it into pieces and they distributed each and they replicated each piece or triplicated each piece and they would send it the pieces of these files to thousands of computers first it was hundreds but then now it’s thousands now it’s tens of thousands. And then they would send the same program to all these computers in the cluster. And each computer would run the program on its little piece of the file and send the results back. The results would then be sorted and those results would then be redistributed back to another process. The first process is called a map or a mapper process and the second one was called a reduce process.