Java is a platform independent programming language created by Sun Microsystems. The development of Java began as part of an internal project at Sun with the idea of creating a language for use with the then future interactive television. Of course, interactive television has yet to take off. The internet, however, did take off and Sun was able to see the need for a platform independent language that could be used to provide a better interactive experience.

Java is a programming language in which the source code gets compiled into a virtual machine language. This machine language is than processed by what is known as a Java Runtime Environment which converts the virtual assembly language into the native machines' assembly language. The theory behind this being that the generic assembly language should be easy to convert into the native machines' assembly language. Early versions of the JRE used interpretation, but the newer versions of JRE use more advanced techniques, such as Just-in-time compilation.

While the use of a virtual machine may make the compiled product able to run on different processors, there is more to multi-platform support than the underlying processor. How the user interacts with the program and how the program accesses system resources is also important. Java relies on a set of standard classes which provide this functionality. Many of these classes, such as the AWT classes, work by calling the native operating system. I will cover the various classes later. It is also possible to expand Java's native support by using JNI. JNI is a way of using platform specific libraries in a relatively platform independent way.

The Java language itself is similar to the C and C++ languages. Those familiar with C++ will have very little problem learning Java. C programmers will have to learn about how object oriented languages work before they can readily take full advantage of Java. Over the next few chapters we will be going over the principles behind the java language.

One thing that seems to be overly common is the confusion between Java and Javascript. Javascript is not java. Javascript is a scripting language created by netscape for use in their browser. While the syntax of javascript is similar to that of Java, they are separate languages and should not be confused for each other.