If you’re not careful about how you include Java applets in your Web pages, people who use browsers that don’t support Java (or who have deliberately switched off Java support) will see nothing where the applet should have been. Be polite and offer non-Java clients an explanation by including alternative HTML code inside the tag pair. For example, you could tell them what they’re missing out on:

 Sorry, your browser couldn't run the Java applet that would normally appear here.
This is because your browser doesn't support Java applets or because its Java support has been switched off.