Hadoop is an open-source framework that allows for the distributed processing of large data sets across clusters of computers using simple programming models. It scales from single servers to thousands of machines, each offering local computation and storage. The framework detects and handles failures at the application layer, providing a highly available service on top of a cluster of potentially fail-prone computers.
Hadoop operates on the principles of distributed computing and storage, utilizing the Hadoop Distributed File System (HDFS) and the MapReduce programming model for efficient data handling and processing across multiple computing nodes.