The Applet is an abbreviated app of the English "application"application and a suffix let that stands for "small". Servlet (Server-let), MIDlet (Mobile Information D Evice-let) and Scriptlet in JSPs are also based on the same principle.
An applet or Java applet is a Java program component that runs on the client in a Web environment. It is also the 1990 's mid-term, Java in the birth of a gun became a hero of fame. Typically, each applet has a single function (for example, just to show a dancing logo), so it is called a "small application."
Applets must be run on a specific "container", either the browser itself or through a variety of plugins, or a variety of other programs, including mobile devices that support applets. Unlike a typical Java application, applets are not run by the main method (see the Hello World program in Java and the Hello World program for Java applets). Applets typically interact with the user at run time, display dynamic footage, and also follow stringent security checks to block potentially unsafe factors (such as restricting access to the client's file system based on security policies).
Java 5 Week Applet