TightVNC is a tightened version of VNC. It provides remote control access to a computer running VNC Server. It works on Windows, Linux and OpenBSD.
When the project first started, it had a lot of features that “RealVNC” did not. I understand that “RealVNC” incorporates a lot of the features that TightVNC has, but I still like to use TightVNC.
You can also tunnel VNC traffic through SSH.