This post explains how to install Java or check which version is running on your machine. Install on any OS, and learn about the JDK.

The JDK is the development platform for building Java applications. Learn about different JDK versions, then install a JDK in your development environment and use it to compile a Java program.

Click on the major version you want to download from the "Java SE" list. For example, choose "Java SE 6" if you want to download any version number ranging from Java 6.0 to Java 6.43.

Need to serve your java apps from a user-friend web app? Look no further than Tomcat. Find out how to install Tomcat on Ubuntu Linux.