There are many online sources for information about Java. Oracle's official web site for Java topics is ; look here for the software, updates, and Java releases. This is where you'll find the JDK, which includes the compiler, the interpreter, and other tools (the JDK is also on the DVD that comes with this tutorial; view the CD content online at ). You should also visit Oracle's Java site at . There you'll find information about other Oracle Java tutorials, and a pointer to the home page for Learning Java, , where you'll find the source code examples for this tutorial.