Top 100 Hadoop Interview Questions for Beginners and Professionals 1. What is Apache Hadoop? Hadoop is an open source software framework for distributed storage and distributed processing of large data sets. Open source means it is freely available and even we can change its source code as per our requirements. Apache Hadoop makes it possible to run applications on the system with thousands of commodity hardware nodes. It’s distributed file system has the provision of rapid data transfer rates among nodes. It also allows the system to continue operating in case of node failure. Trending and Updated Hadoop Topics - FREE PDF Download 2. Main Components of Hadoop? Storage layer – HDFS Batch processing engine – MapReduce Resource Management Layer – YARN HDFS – HDFS (Hadoop Distributed File System) is the storage unit of Hadoop. It is responsible for storing different kinds of data as blocks in a distributed environment. It follows master and slave topology. MapReduce