JRE and JDK

Java SE Runtime Environment (JRE)

Oracle provides two principal software products in the Java™ Platform, Standard Edition (Java™ SE) family:

The JRE provides the libraries, Java virtual machine, and other components necessary for you to run applets and applications written in the Java programming language. This runtime environment can be redistributed with applications to make them free-standing.

Java SE Development Kit (JDK)

The JDK includes the JRE plus command-line development tools such as compilers and debuggers that are necessary or useful for developing applets and applications.