JDK Vs JRE Vs JVM

JDK is a kit(or package) which includes two things i) Development Tools(to provide an environment to develop your java programs) and ii) JRE (to execute your java program). JDK is only used by Java Developers.

JRE (Java Run-time Environment) helps in running the programs. JRE contains the JVM, the java classes/packages and the run-time libraries. If we do not want to write programs, but only execute the programs written by others, then JRE alone will be sufficient.

JVM Java Virtual Machine is important part of the JRE, which actually runs the programs (.class files), it uses the java class libraries and the run-time libraries to execute those programs. Every operating system(OS) or platform will have a different JVM.