Working model of Mapreduce : Quick start guide for Mapreduce Programming

Map Reduce is a programming model by which large data set is processed in a parallel and distributed manner on a cluster .

This concept is first introduced by Google and later, it became part of Apache.

The processing unit of Mapreduce model is key-value pair. This model processes large data sets whether structured or unstructured and generates key-value pairs.

Generally Mapreduce consists of two phases.