Distributed File System
Apache(TM) Hadoop(R) is a library framework that facilitate using a network of many computers to solve problems involving massive amounts of data and computation providing for distributed storage and processing of big data using the MapReduce programming model. It is designed to scale up from single servers to thousands of machines, each offering local computation and storage. Rather than rely on hardware to deliver high-availability, the library itself is designed to detect and handle failures at the application layer, so delivering a highly-available service on top of a cluster of computers, each of which may be prone to failures.