Storm is an open source distributed real-time processing system that allows efficient processing of large streams of data. It uses a master-slave architecture where the Nimbus node is the master that coordinates the Supervisor nodes which run worker processes, and Zookeeper helps coordinate communication between all nodes. To use Storm, you install it, configure Zookeeper and Nimbus/Supervisor nodes, then start the processes in the correct order - Nimbus, Supervisor, UI to view topologies. Storm processes data in tuples through topologies defined by spouts and bolts.