If you are new to programming, you may be asking yourself what is the JDK? In short, the JDK contains a set of libraries and utilities for developing Java applications. It also comes with the Java Runtime Environment, also known as the JRE. In addition, you will also hear the term Java Virtual Machine or JVM used to refer to the JRE.

If you are coming from another programming language like say .NET, then you can think of the JDK to be similar to the. NET runtime in that it provides the environment for you to write and run your code.

If you have been developing in Java, then I'm sure you can skip this explanation and move on to the next one :)