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).
Now days, new monitors have a 60 Hz Refresh Rate that gives you the option to change the Refresh Rate up to 70 Hz, if your monitor is compatible. A high performance monitor can set the Refresh Rate to 120 Hz. If your Monitor Rate is higher, your display is better and very comfortable. If you want to change the Refresh Rate then do that in the Control Panel. Windows selects the best display settings such as Screen Resolution, Refresh Rate and Color.