VNC stands for Virtual Network Computing. It is remote control software which allows you to view and interact with one computer (the "server") using a simple program (the "viewer") on another computer anywhere on the Internet.
The two computers don't even have to be the same type, so for example you can use VNC to view an office Linux machine on your Windows PC at home. VNC is freely and publicly available and is in widespread active use by millions throughout industry, academia and privately.
This version includes both the VNC server and viewer.
Update to VNC Viewer only. Patches a possible security vulnerability only present in the listening viewer. VNC Server is not compromised.