These tools use Java Web Start technology.
Java Web Start is an application-deployment technology that gives you the power to launch
full-featured applications with a single click from your Web browser.
Java Web Start includes the security features of the Java platform, so the integrity of your
data and files is never compromised. In addition, Java Web Start technology enables you to use
the latest Java SE technology with any browser.
With Java Web Start, you launch applications simply by clicking on a Web page link. If the
application is not present on your computer, Java Web Start automatically downloads all necessary
files.
It then caches the files on your computer so the application is always ready to be
relaunched anytime you want either from an icon on your desktop or from the browser link.
And no matter which method you use to launch the application, the most current version of
the application is always presented to you.
The use of these tools requires the installation of the latest Java Virtual Machine (JRE) if not yet
installed on the PC.
You can download the JRE here
http://www.java.com/en/download/manual.jsp