Video Resolution and Refresh Rate
Digital displays have many specifications to consider. The resolution of the display largely determines the amount of detail that can be placed on screen, and refresh rate determines how often that image is updated.
Higher resolutions and refresh rates will require more data to be sent to the display. Limits on these specifications largely come from bandwidth limitations of the display output port being used, or in the case of DisplayLink, the bandwidth required to send compressed video data as USB data.
Display resolution is expressed in many different ways. To make things easier, we try to stick to commonly-accepted abbreviations for maximum resolutions outside of detailed specifications.
In product specifications, we state all resolution options for horizontal and vertical pixels that can be displayed, as well as the maximum refresh rate at the resolution:
Width (in pixels) x Height (in pixels) @ Refresh rate in hertz
A display's refresh rate indicates how many times per second that the image on the display is updated, and is typically expressed in hertz (Hz). Most inexpensive computer displays will have a 60Hz refresh rate, and there are displays that operate at both higher and lower rates. Higher rates generally offer added smoothness to motion on screen, making animations and scrolling actions appear more fluid.
Early 4K monitors typically have a 30Hz refresh rate, motion pictures typically have a 24Hz refresh rate, and broadcast television in the United States is usually offered at 30Hz.