Java can be used to create two types of programs: applications and applets.
An application is a program that runs on your computer, under the operating system of that computer. When used to create applications, Java is notuch different from any other computer language.
An Applet is an application designed to be transmitted over the Internet and executed by a Java-compatible Web browser. An applet is actually a tiny program, dynamically downloaded across the network, just like an image, sound file, or video clip. The important difference is that an applet is an intelligent program, not just an animation or media file.