An applet is a program, written in the Java programming language, that was designed to be run in a web browser. The browser uses an extension (called a JRE -- Java Runtime Environment) to run the applet.

Because of security concerns, some browser makers have disabled the JRE extension, meaning those browsers will no longer run applets embedded on web pages.

So now we are opening our applets outside of the web page, using JavaWS (Java Web Start).

These applets are launched outside the browser, but they are unchanged, and they are still subject to the same sandbox restrictions as when they were run within the browser. The signed certificate that you are asked to accept when opening the applet confirms that these are the unchanged, original applets, written by us at NRRI.

When you click a link for a data viewer, you will download a small app that is used to launch the applet -- a ".jnlp file" (Java Network Launching Protocol).

Some browsers can launch the app directly when the link is clicked. All browsers will let you save these files, which you can then open as you would any app on your computer -- even if your browser is closed!

Note: As before, you will need to have a JRE (Java Run-time Environment) installed on your computer. You should use the most recent version of the JRE to avoid security vulnerabilities discovered in older versions.

If you need to install a JRE you can do so at java.com. More information on installation and troubleshooting is available on their troubleshooting page.