Java is very powerful saftware platform. More than that it is platform independent. Java is Object Oriented language. Java is mainly used for following purpose
Java can be used to develope web based application along with stand alone application.
Using swing & Java 2D toolkit we can create sofisticated GUI
The JDK provides standard mechanisms, such as Java Web Start and Java Plug-In, for deploying your applications to end users.
Java also provides integration libraries such as JDBC, JNI,RMI etc for database access & remote object manipulation.
With J2EE (Java 2 Enterprise Edition)we can we can develope enterprise application
The Java Platform, Micro Edition (Java ME) provides a robust, flexible environment for applications running on consumer devices, such as mobile phones, PDAs, TV set-top boxes, printers and a broad range of other embedded devices.