The Content Management System we use at the office is written in Java, so on the development systems, we need to be careful to match the JDK version to the JRE version used by the CMS vendor. Periodically someone new will join the team, and they end up wondering what a JDK is and how is that different from a JRE?
So let’s break this down. Generally speaking, an SDK or Software Development Kit. Basically, it’s the set of compilers, debuggers, and other tools used for creating software on a given platform.
That’s basically what the JDK is. The Java Development Kit contains compilers, debuggers and other tools for creating Java applications.
While a software (or Java) development kit allows you to create software, some software platforms also require a runtime environment. The JRE, or Java Runtime Environment is the support software that allows a Java application to execute.