An operational amplifier, or op-amp, is a versatile electronic component used to amplify voltage signals. It typically has two input terminals, inverting and non-inverting, and one output terminal. Op-amps are widely used in various applications, including signal processing, filtering, and mathematical operations like addition and subtraction. Op-amps can be configured in different ways, such as inverting and non-inverting amplifiers, to achieve desired gain and functionality. They are characterized by high input impedance and low output impedance, making them ideal for interfacing with other components in electronic circuits.