Java Applet / Plug-in

Java Applet就是用Java语言编写的小应用程序，可以直接嵌入到网页中，并能够产生特殊的效果.

1. Applet被下载到用户的计算机上执行.
2. Applet还提供了名为抽象窗口工具箱（Abstract Window Toolkit， AWT）的窗口环境开发工具.
3. 含有Applet的网页的HTML文件代码中部带有<applet> 和</applet>这样一对标记.
3. Applet不需要main()方法，由web browser中内嵌的JVM执行.
4. Applets are designed just for handling the client site problems. while the java applications are designed to work with the client as well as server. 

Java Plug-in Technology

Java Plug-in technology, included as part of the Java Runtime Environment, Standard Edition (Java SE), establishes a connection between popular browsers and the Java platform. This connection enables applets on Web sites to be run within a browser on the desktop.

 

So, to run applets on a browser, you have to install JRE, which contains Java Plug-in.