Your Guide to Java:
The Java Platform

The Java platform or runtime environment is the platform that enables Java applications and applets to run on any system regardless of the operating system and underlying hardware.

Rather than compiling code into a format designed for a specific platform, developers compile Java source code into an intermediate form, bytecode, which can be executed on any system with a runtime environment.

The Class Loader transfers the Java bytecode to the Java Virtual Machine (JVM). The heart of the Java platform, the JVM is basically a "soft" CPU that sits between applications and the platform (operating system and hardware). The JVM interprets bytecode for the platform or uses a just-in-time (JIT) compiler to convert the bytecode to machine code for that specific platform. Java class libraries�the files that make up the standard API (application programming interface) for applications and applets�are also loaded dynamically as needed.

The runtime system (which manages threads, memory, and other system resources) then executes the interpreted or machine code on that platform. The program may be run within a browser (applet) or as a standalone application.

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