Virtual Network Computing (VNC) technology allows a copy of one computer's screen to be shared with another computer over a network connection. VNC, also known as remote desktop sharing, is typically used by people who want to monitor or control a computer from a remote location rather than simply access shared files.

The following free software packages provide VNC functionality. VNC software consists of a client user interface plus a server that manages connections to clients and sends desktop images. Some applications support only Windows PCs, while others are portable across several types of network devices.

The TightVNC Server and Viewer use special data encoding techniques designed to better support lower speed network connections. The latest versions of TightVNC, first released in 2001, run on all modern Windows flavors, and a Java version of the Viewer is also available.

The creation of TigerVNC software was initiated by Red Hat with the goal of improving TightVNC. TigerVNC development began with a snapshot of TightVNC code and has expanded support to Linux and Mac in addition to Windows, plus several performance and security improvements.