How are JRE, JVM and JDK different

JVM, Java Virtual Machine - the main part of the Java Runtime Environment (JRE). The Java Virtual Machine runs Java bytecode that is previously generated from the Java source by the Java compiler. The JVM can also be used to run programs written in other programming languages.

JRE, Java Runtime Environment, is the minimum required virtual machine implementation to run Java applications. Consists of JVM and standard set of Java class libraries.

JDK, Java Development Kit - JRE and a set of tools for developing applications in the Java language, including the Java compiler, standard Java class libraries, examples, documentation, various utilities.

In short: JDK is an environment for developing programs in Java, which includes JRE - an environment for ensuring the launch of Java programs, which in turn contains a JVM - an interpreter for Java programs.

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