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).
To display 25 frames per second on a TV with a 50 hz refresh rate (PAL Countries), each frame is repeated 2 times every 25th of a second. To display 25 frames per second on a TV with a 100 hz refresh rate (PAL Countries), each frame is repeated 4 times every 25th of a second.