The NOT gate is a single input single output gate. This gate is also known as Inverter because it performs the inversion of the applied binary signal, i.e., it converts 0 into 1 or I into 0.The logic symbol for the gate is shown below.
The symbol of the not gate is a triangle with bubble on its end. This bubble is known as the inversion bubble. It gives the complement of the input signal. It is also known as the decision making devices becasue it has only one input.The switching circuit diagram of the NOT gate is shown below.
The truth table of the gate is given below.