Apache Hadoop is an open source framework used for distributed storage as well as distributed processing of big data on clusters of computers which runs on commodity hardwares. Hadoop stores data in Hadoop Distributed File System (HDFS) and the processing of these data is done using MapReduce. YARN provides API for requesting and allocating resource in the Hadoop cluster.
This is a companion discussion topic for the original entry at https://linuxconfig.org/how-to-install-hadoop-on-redhat-8-linux