Circuit with AND gate
Two switches on, the bulb lights up.
One switch off and one on the bulb will not light up.
Truth table - AND gate
Made up of binary.The first switch is input A, The second switch is input B. So if input A is off or 0 and input B is off or 0 the bulb will be off or 0. If input A is off or 0 and input B is 1 or on the light bulb will not be on. However if both inputs are on or 1 the light bulb will be on.