Hadoop is a reliable system for shared storage and analysis with a rich ecosystem of layered solutions and tools for Big Data. Hadoop is built on the concepts of distribution for storage and computing. It is a cross-platform, Java-based solution. Hadoop can run on a wide array of different operating systems, such as Linux and Windows, because it is built in Java, a platform-neutral language. Hadoop itself is a layer that sits on top of the host operating system. Hadoop's core functionalities are also built in Java and can be run as separate processes. With its own filesystem and set of core functionalities, Hadoop serves as its own abstract platform layer; it can be accessed and run almost entirely independent of the host operating system.

The following figure shows a high-level representation of the Hadoop layers:

Figure 1: The Hadoop architecture layers

The Hadoop layers are an abstraction for how the various components are organized and the relationship between the...