The Java Runtime Environment, or JRE, or J2RE is software created by Sun Microsystems that allows a computer system to run a Java application.

Overview

A JRE is required to run Java applications interpretively on a target hardware and operating system platform, since Java applications are not in machine code. Many applications for which a degree of portability is important are written in Java, and some Web pages use Java as well. (Java should not be confused with Javascript, which is much more widespread on the Web and is interpreted directly by Web browsers, without the need for a runtime environment.)

As of 2007 computer users can download the current JRE version (Sun lists JRE 6.0, JRE 1.5 and JRE 1.4) by testing their Java Virtual Machine (JVM) at the Java.com test page.

The software bundle consists of the JVM and programming interface (API). The API provides a set of standard class libraries. The virtual machine and API have to be consistent with each other and are therefore bundled together as the JRE. This can be considered a virtual computer in which the virtual machine is the processor and the API is the user interface.

External links

• Java Runtime Environment Download from Sun Microsystems
• Java Runtime Environment Download from Java.com
• Java SE Downloads
• Test your Java Virtual Machine (JVM)

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Sun technologies	Java (programming language) · Java Platform · Java Development Kit · Java Virtual Machine · Java Runtime Environment
Third-party technologies	GNU Classpath · GNU Compiler for Java · Apache Harmony · Kaffe
History	Java version history · Criticism of Java · Java Community Process · Sun Microsystems · Free Java implementations
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