VNC stands for Virtual Network Computing. It is, in essence, a remote display system which allows you to view a computing `desktop' environment not only on the machine where it is running, but from anywhere on the Internet and from a wide variety of machine architectures.
This is the vnc java applet files that the vnc-server can distribute to the client.
It also includes the TightVNC patches from http://www.tightvnc.com/