The number of times in a second that display hardware draws the data, refreshing the image. Refresh rates for broadcast TV vary by region – for example, European HD systems run at 50 Hz.
On CRT displays, increasing the refresh rate decreases flickering, thereby reducing eye strain. However, if a refresh rate is specified that is beyond what is recommended for the display, damage to the display can occur.
Refresh Rate is distinct from the measure of frame rate in that the refresh rate includes the repeated drawing of identical frames, while frame rate measures how often a video source can feed an entire frame of new data to a display.