JDK, JVM, JRE - Understanding Terminology

JDK, JVM, JRE - Know the relationship between them.

JVM - Java Virtual Machine is an abstract computing environment.

JVM becomes useful when we have an implementation plus utility classes which is called JRE - Java Runtime Environment. Utility classes help to get current date and time, to generate a random number etc.

Feeding the JRE (or JVM):

Class files (also called Byte Code) must be generated  from Java source files for which we need a compiler.  Thus the JRE plus tools needed by a developer like compiler, debugger etc together is called JDK - Java Development Kit.

The below picture provides the summary of the relationship between them.