The only difference between the Hz and kHz is like that of meter and kilometer. Hz is the unit of frequency and the kHz is the unit in the multiple of thousand. 1 kHz is equal to almost 1000Hz.
HZ means hertz and used to measure frequency (number of events per second). Hertz is a SI unit for frequency. KHZ means Kilohertz and it is a commonly used multiple.
1kilohertz, 103 Hz.
1kilohertz, 103 Hz.