Samsung SyncMaster 740BX Owner's Manual page 66

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