Hadoop :- Hadoop is an open-source software framework for distributed storage and distributed processing of extremely large data sets.

Important features of Hadoop are :-

• Apache Hadoop is an open source project. It means one can modify its code for business requirements.

• In Hadoop, data is highly available and accessible despite hardware failure due to multiple copies of data. If a machine or any hardware crashes, then we can access data from another path.

• Hadoop is highly scalable, as we can easily add the new hardware to the node. Hadoop also provides horizontal scalability which means we can add nodes on the fly without any downtime.

• The Hadoop is fault tolerant as by default, 3 replicas of each block are stored across the cluster. So if any node goes down, data on that node can recover from the other node easily.

• In Hadoop, data is reliably stored on the cluster despite machine failure due to the replication of data on the cluster.

• Hadoop runs on a cluster of commodity hardware which is not very expensive.

• Hadoop is very easy to use, as there is no need of the client to deal with distributed computing; the framework takes care of all the things.

But as all technologies have pros and cons, similarly there are many limitations of Hadoop as well.