VNC Server is an app to allow running a desktop environment in your HDA even when it is headless (without a monitor). It is the program on the machine that shares its screen. The server passively allows the client to take control of it. You need one of the many VNC client programs available that can talk the VNC protocol.
VNC is platform-independent VNC viewer on one operating system may connect to this VNC server app on the same or any other operating system. There are clients and servers for many GUI-based operating systems and for Java. In some cases, multiple clients may connect to a VNC server at the same time. Popular uses for this technology include remote technical support and accessing files on one's work computer from one's home computer, or the other way around. Client software includes:
- Windows: RealVNC, UltraVNC, TightVNC
- MAC: Chicken of the VNC, or the internal Apple remote desktop client
- For Linux, you have the vncviewer package, available in most, if not all distros. It may be called tigervnc
NOTE: By default, VNC is not a secure protocol. While passwords are not sent in plain-text, brute-force cracking could prove successful if both the encryption key and encoded password are sniffed from a network. For this reason it is recommended that you only use VNC within a trusted network, with trusted clients or through a secure connection like VPN.