The end-user, the platform offers a live, interactive content on the World Wide Web, and just in time for the software to use. Applications are available on all operating systems at once.Java keeps a good compatibility to earlier versions. That means, your Java-projects are compile and run in most cases without any problem on newer versions. That seems to be a little point, but this stability in API's and language helps to build a big community around Java, including good tool-support.
Others already mentioned other important points:
- good portability
- lot's of libraries for nearly anything
- easy debugging and easy to catch problems