Samsung KS17LBKWK-TRU - Manual (Page 47)

Horizontal Frequency
The time to scan one line connecting the right edge to the left edge of
the screen horizontally is called Horizontal Cycle and the inverse
number of the Horizontal Cycle is called 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 Vertical Frequency or Refresh
Rate. Unit: Hz