Introduction to Java
Developed by Sun Microsystems, Java is an object oriented programming language (OOP) that can be used for general purpose business programs and interactive WWW based Internet programs. It is architecturally neutral or platform independent - can write programs on any platform or operating system.
Java comes with a library of classes to perform common tasks. The Java class library is organized into a set of packages, each containing a collection of related classes. These classes contain objects (instance of classes), methods (functions to perform some action), and data fields (containing a value).
There are some packages that are imported automatically. They contain such classes as String and System (described below). You can also import other classes or packages (like including header files).