Not long ago, the only time you could see a robot was when you were reading a novel or watching a movie such as Star Wars (星球大战) . Today, however, a lot of things in science stories have been science facts. Robots are starting to appear in our everyday lives. These robots have different sizes, shapes, and colors. But they all have the same type of man-made “brain”. Leading the robot revolution （革命）are industrial(企业) robots that work in factories. Industrial（工业） robots can do different kinds of jobs that are often boring and sometimes dangerous. Robots are also coming to American homes, though not as quickly as they are entering factories. These robots aren’t as friendly and bright as those you saw in  Star Wars. But, their makers say, today's home robots “walk”, sense objects(感知物体) in their way (and sometimes knock into them), and even carry objects (which they sometimes drop). Well, nobody is perfect.
    We may laugh at home robot today, but some day they may see and hear better than humans do. We humans can only see certain wavelengths（波长） of light, and hear certain sounds. That’s because the abilities of our eyes and ears are limited. Robots, however, need not have the same limits as we have. Robot may also be equipped with devices that pick up information humans can't. To understand what their sensing devices(传感器) pick up is a hard job. Remember, man—made brains handle(处理)information, including all kinds of data, as zeroes and ones. Imagine the difficulty in trying to explain to a robot what a football looks like—using only zeroes and ones.