What is Java ?

Before you want to remove the first 2 Java Runtime, you can use paper or a text file to write down the version of these Java Runtime. Then you can remove them. If you cannot run any Java Applet and you are very sure you need the runtime 1 or 2, You can install it again. You can download Java runtime from http://java.sun.com.
1.Java 2 Runtime Enviroment sev 1.4.2-03 128mb
2.Java(TM)6 update 3 135mb

Are you using Windows or Linux OS?

http://www.java.com/
http://en.wikipedia.org/wiki/Java_(programming_language)

Please browse the above webpages to learn what is java.

Java是一種類似Microsoft的免費軟件，
但功能當然不能和Microsoft比媲。
因為Microsoft是要購買的，
而Java是免費功能當然會較為差。