With an Applet running under the control of an HTML browser, it’s natural to provide Help in the form of an HTML file too, or a set of them for a complex task. If your Applet’s interface is displayed in a separate Frame, then you can safely use the browser’s window for the Help with the following lines of code;

 import java.net.*;    try {        URL docubase = getDocumentBase();        URL helpfile = new URL(docubase, "YourHelp.html");        AppletContext browser = getAppletContext();        browser.showDocument(helpfile);    }    catch (Exception ex) {}

If the Applet’s interface is displayed in the browser’s window, then you can trigger the creation of a second window for the Help file by having another argument in the showDocument method;

         browser.showDocument(helpfile, "Help");

With most popular browsers, this second argument will be used as the window’s title. If you implement context sensitive help, displaying one of several HTML files, then using the same second argument each time will result in re-use of the same window.