I have a Lock-In amplifier that can generate sinusoidal signals up to 1.5V peak. There is an output port and input port, and I can obviously fix the frequency or amplitude of the signal I am sending out from the output port.

This device also has a switchable input port impedance and an output load impedance too. The input port impedance can switch between 50 ohms and 1M ohms. The output impedance can switch between 50 ohms and "HiZ"?

This is the description I got for the output impedance being turned on or off:

"Select the load impedance between 50Ω and HiZ. The impedance of the output is always 50Ω. For a load impedance of 50Ω, the displayed voltage is half the output voltage to reflect the voltage seen at the load."

I'm still learning some AC circuiting, so I was hoping if someone could explain me or point me in the right direction to try understand the point of this better.

Thanks a lot for your help