Wednesday, December 19, 2001 02:31 PM
JDK is Java Development Kit which contains all the necessary tools to compile,run and monitor running java byte codes.
JRE is Java Runtime Environment needed to just run the java byte code.
plug-in is the component of the JRE which is added to the HTML browser which would meet all the interface requirements of the browser so that you could run applets in the browser.
What is appropriate (JDK or the JRE ) depends on what you want to do with it. If you have the JDK, you have it all! Do you want to compile java code or just run compiled code?
You could have more than one version of JDK/JRE in the same machine.