The time to scan one line connecting the right edge to the left edge of the
screen horizontally is called the Horizontal Cycle and the inverse number
of the Horizontal Cycle is called the Horizontal Frequency. Unit : kHz
Vertical Frequency
Like a fluorescent lamp, the screen has to repeat the same image many
times per second to display an image to the user. The frequency of this
repetition is called the Vertical Frequency or Refresh Rate. Unit : Hz