This project uses two Infrared (IR) obstacle sensors o notice the direction of movement; if the direction is from left to right otherwise known as the entrance, it will count that the person has moved inside a house. And would keep increasing the number of person moving into the house direction according to this motion, Once the entrance count is above one (1), it will turn on an AC bulb. But if the direction of movement was from ight to left (Exit movement) it will decrement the number of count of people inside the house and will keep decrementing according to this directional motion until the count is zero and it will turn off the AC bulb.