Nao is an autonomous humanoid robot designed by Aldebaran Robotics. He has optic sensors, audio sensors, and in certain places, such as the front torso, and top of head, he has impact Sensors. He is not very big (only about 23 inches tall). He has Wi-Fi that gives him the ability to converse directly with another Nao unit. The Nao robot replaced Sony's robotic dog AIBO in the RoboCup competition.