Applets are Java programs that run in web browsers. They are embedded in web pages and run on the client side. When an applet starts, the init(), start(), and paint() methods are called sequentially. When it terminates, the stop() and destroy() methods are called. Applets do not use a main method but are instead automatically called. They allow moving work from the server to the client and are cross-platform, but require the Java plugin and may not run on all browsers.

1. Introduction
 Applet is a special type of program that is embedded
in the webpage to generate the dynamic content.
 It runs inside the browser and works at client side.
 It can be executed by browsers running under many
platforms, including Windows , MacOS etc.
 Plug-in is required at client browser to execute applet.
 Applets don’t use the main method, but when they
are load, automatically call certain
methods(init,start,paint,stop,destroy).
 They are embedded inside a web page and executed
in brow

2. Life-Cycle
When an applet begins, the following
methods are called, in this sequence:
1. init( )
2. start( )
3. paint( )
When an applet is terminated, the
following sequence of method calls
takes place:
1. stop( )
2. destroy( )

3. Example
import java.applet.Applet;
import java.awt.Graphics;
// HelloWorld class extends
Applet public class HelloWorld extends Applet {
// Overriding paint() method
public void paint(Graphics g) {
g.drawString("Hello World", 20, 20);
}
}
java HelloWorld Error:
Main method not found in class HelloWorld, please define
the main method as: public static void main(String[] args)
ERROR:

4. Exp.Solution
There are two standard ways in which you can run an
applet :
1. Executing the applet within a Java-compatible we
browser.
2. Using an applet viewer, such as the standard tool,
appletviewer
<applet code="HelloWorld" width=200 height=60> </applet>
appletviewer RunHelloWorld.html

5. Adv./Disadv.
Advantage:-
• It is simple to make it work on Linux, Microsoft
Windows and OS X i.e. to make it cross platform.
• The same applet can work on “all” installed
versions of Java at the same time.
• It can move the work from the server to the client.
• Secured:-An un-trusted applet has no access to the
local machine and can only access the server it
came from.
• Java applets are fast.
Disadvantage:-
• It requires the Java plug-in.
• Some browsers, notably mobile browsers
running Apple iOS or Android do not run Java
applets at all.
• Some applets require a specific JRE.