What is a function generator?

A function generator is a piece of electronic test equipment that generates a variety of periodic voltage signals such as sine waves and square waves. There are three controls on the face of the device that allow the user to control 1) the type of waveform (sinusoid or square), 2) the frequency of the periodic signal, 3) and the amplitude of the signal. There are two terminals on the control panel. The black terminal is for ground and the red terminal is the desired voltage waveform.