What is the primary function of an operational amplifier?

The primary function of an operational amplifier is to amplify the difference in voltage between its two input terminals. This is fundamental to how operational amplifiers operate in various applications. They take two input voltages—usually referred to as the inverting and non-inverting inputs—and produce an output voltage that is proportional to the difference between these two inputs, multiplied by the amplifier's gain.

This capability allows operational amplifiers to be used in numerous circuits, such as amplifying weak signals, performing mathematical operations like addition or subtraction, and serving as building blocks for filters and oscillators. Their ability to process voltage differences makes them essential components in analog electronics, effectively facilitating signal manipulation and processing.