Hadoop is an open-source framework used to store data across many computers in a distributed environment. The 3 core components of Hadoop are Hadoop Distributed File System (HDFS), MapReduce, and Yet Another Source Negotiator (YARN). HDFS, a file system of the Hadoop cluster, handles large data and provides scalable data storage running on commodity hardware. It also facilitates compatibility across various underlying operating systems. MapReduce is basically a programming model used to process and generate large data sets across multiple machines. YARN was introduced as an improvement over Job Tracker. It facilitates many data processing engines to process data stored in HDFS.