Java 6, also known as Java SE 6, is a version of the Java programming language released by Sun Microsystems in December 2006. It introduced several enhancements, including improvements to the Java Virtual Machine (JVM), better performance, and new features like the Java Compiler API and support for scripting languages through the Java Scripting API. This version also focused on improving the development experience with tools like Java DB and enhancements to the Java Platform, Standard Edition libraries. Overall, Java 6 aimed to make Java more efficient and easier to use for developers, paving the way for future updates.