Java Plug-in now supports the HTML APPLET tag for launching applets. Users may configure their browsers so that JRE 1.4.0 is the default runtime environment for handling APPLET tags.
For developers, the Java Plug-in enhancements enable you to deploy your applet web pages without the need for an HTML Converter or the use of OBJECT tags, while still being able to ensure that your users will have the latest JRE/Java Plug-in for running your code.
Even though Java Plug-in now supports the APPLET tag, it does not support applets that make use of proprietary technologies. Examples of such technologies are
CAB files
Authenticode signing
Java Moniker