Cyril
Sorry, replied to your question but wrote the code for the applet tag directly into the answer. I thought this would be fine if I enclosed it in code tags, but apparently I was wrong. Hence, completely disregard the mess you see above this post. The applet tag confuses things, so I won't put a literal example in this post.
Anyhow, the problem is you need to supply some attributes within the applet tag in your html. At a minimum,
you should include height and width, plus the code attribute, which is the one causing your current problems. This attribute specifies the name of the Java class that extends Applet e.g. "MyApplet.class"
A good book for beginning Java? I found both "Java In A Nutshell" by David Flanagan on O'Reilly and "Java 2 How To Program" by Deitel & Deitel on Prentice Hall to be pretty useful. The Deitel book in paticular covers many different aspects of the language at an introductory level, and is full of examples of code.
Hope this helps
Michael
[This message has been edited by Michael Fitzmaurice (edited September 17, 2001).]