It is an open source software framework that enables reliable and scalable storage and processing of large datasets in a distributed environment.
Here is the definition provided on the official Apache Hadoop's website:
"The Apache Hadoop software library is a framework that allows for the distributed processing of large data sets across clusters of computers using simple programming models. 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."
It has been designed to handle hardware-level failures at the application layer itself, and this is one of the prime features that enables use of commodity hardware as part of the clusters crunching data using...