Which function indicates the opposite of an input signal in electrical logic?

The function that indicates the opposite of an input signal in electrical logic is the NOT function. This function performs a logical negation, meaning it takes a single input signal and outputs the opposite value. If the input is true (or 1), the output will be false (or 0), and vice versa. This characteristic of inverting the input makes the NOT function essential in digital circuits, particularly for creating logical conditions and controlling the flow of logic in combinations with other gates.

In the context of electrical logic, understanding how the NOT function works is vital for designing circuits that require specific signal inversions, which can be used in various applications such as control systems and data processing. It contrasts with other logical functions like OR, AND, and NAND, which do not solely invert input signals but operate based on a combination of inputs and predefined logical rules.