JAVA_HOME is an operating system (OS) environment variable which can optionally be set after either the Java Development Kit (JDK) or the Java Runtime Environment (JRE) is installed.

Setting the PATH variable allows you to launch programs via CLI from anywhere on your system. Here's how to set the PATH variable in Windows and make the most of it.

If you want to play around with a Java preview feature, you'll first need a Java Development Kit. Here's how to install JDK 13 on Ubuntu and set the all-important JAVA_HOME variable.