Intro To Java - The Big 3

The Java Development Kit (JDK), is, as the name implies, what you need if you want to develop a Java app. It is required for debugging, testing, and finding errors in your code. It also includes the Java Compiler. I will explain the Java compilation process in "Java Compilation and Execution".

The Java Runtime Environment (JRE) contains the libraries that come with Java. These libraries contain functionality that you can use in your own Java code. It also includes the JVM (explained next). The JRE is required to run Java programs. The JRE is usually bundled with the JDK, allowing both development and execution. This bundle is what we installed in the previous lesson.

The Java Virtual Machine (JVM) is used to execute a compiled Java program. It is part of the JRE. I will explain specifically what it does in "Java Compilation and Execution".