The Obstacle Avoidance Tracking Sensor is a versatile and easy-to-use device that can be integrated with Arduino or other microcontrollers. It consists of an infrared transmitter, an infrared receiver, and a potentiometer to adjust the sensitivity. The sensor can detect obstacles within a range of 2cm to 30cm by emitting and receiving infrared light. When an obstacle is detected, the sensor outputs a LOW signal. When no obstacle is detected, the sensor outputs a HIGH signal. The sensor can also track lines by distinguishing between dark and light colors. When the sensor is over a dark color, the sensor outputs a HIGH signal. When the sensor is over a light color, the sensor outputs a LOW signal. The sensor can be used to make remote controlled vehicles stop or change course automatically if they come close to hitting an object, or to guide them along a dark colored line on the ground. The sensor is compatible with various platforms such as Arduino, Raspberry Pi, STM32, etc. The sensor is suitable for projects such as smart cars, robots, line followers, obstacle avoiders, etc.