An inverter is a type of logic gate that performs logical negation. In other words, it takes an input signal and produces an output signal that is the opposite of the input. For example, if the input is 1 (or high), the output will be 0 (or low), and vice versa. Inverters are often used in digital circuits to perform logical operations such as AND, OR, and NOT. They are also commonly used to convert a digital signal to an analog signal, or to convert an analog signal to a digital signal.