Mini DisplayPort is a compact version of the DisplayPort connector introduced by Apple in 2008. Mini DisplayPort is free to license, and in 2009 it was included in the official DisplayPort 1.2 spec. In 2011 Apple and Intel announced the Thunderbolt format, which used the same physical connector, but significantly different protocols.
Screen refresh rate is the number of times an image on any type of monitor or television is reconstructed per second. This is measured in hertz.. (Hz).
The beauty of both the 120hz and the 240hz refresh rates is that both 24 and 30 can be divided into them evenly. If you are viewing a 24fps show on your 120hz television, each frame of the 24 will be displayed 5 times a second (24 x 5 = 120).