Hadoop is managed by apache software foundation and licensed under the Apache license 2.0 Hadoop is very useful for the big data business. It is a java based open source framework. It is less expensive to store and process data because it is based on cost effective servers. Hadoop is extensively used in security and law enforcement to prevent cyber-attacks, tech behemoths use it for drawing data conclusions for customer requirements, governments use Hadoop to plan and develop smart cities, improving healthcare facilities etc. It is a must know skill for ambitious IT professionals who want to work in big data as data scientists.