# Logic Gates Explained – AND, OR, NOT, NAND, NOR, XOR, XNOR

The logic gates are digital circuits which are the fundamental building block of logical-implementation (microprocessors, microcontrollers etc.).The relationship between the input and the output is based on a certain logic.

The basic logic gates are AND, OR and NOT; which are used to generate simple yet the rudimentary digital ckt that is a flip-flop, adder, subtracter etc. etc.It is the basic combination of transistors(and resistances if you are thinking BJT implementation) which can “make sense” or implement logic. Logic gates involve decision making in the world of Electronics.

From the school days were taught about major 4 arithmetic functions Addition, Subtraction, Multiplication and division. But we are also using other than these arithmetic function few logic functions day to day life.

For example –  Conditional statements like – if someone is present in the room, switch ON the light otherwise switch OFF the light. Here we use the OR function. The light will only be switched on if there are people present in the room else it’ll remain off. This is a logical function.The same way, let us take another example –  if person A  AND person B both arrive at the stop then start the bus i.e if both the persons will come then and then only the bus will start. Here we used AND function.

Let Us Understand The Logic Gates In More Precise Way-