The Java Platform is the name for a computing environment, or platform, from Sun Microsystems which can run applications developed using the Java programming language and set of development tools. In this case, the platform is not a specific hardware or operating system, but rather an execution engine called a virtual machine, and a set of standard libraries which provide common functionality.

The platform is properly called the Java Platform (formerly Java 2 Platform), and includes the Java Platform, Standard Edition or Java SE (formerly J2SE), the Java Platform, Enterprise Edition or Java EE (formerly J2EE), and the Java Platform, Micro Edition or Java ME (formerly J2ME). As of 2006, the current version of the Java Platform is alternatively specified as version 1.5 or version 5.0 or version 5 (all refer to the same version), however, version 5 is the preferred reference.