Piezo buzzer is a small tiny device that produces sound signals. It is used in projects for alarms, tone generations, etc. A buzzer can only make sound tones and can?t make a voice like speakers do. Using PWM Signals the tone of the buzzer can be varied. This buzzer is breadboard compatible and can be directly plugged into a breadboard.
A different tone delay and combinations are used to notify a type of alarm signal. You might have heard this buzzer sounds in ATM Vending machines, Induction stoves, Washing Machines, Bike Stand alarms, etc. It is cheaper and has many uses.