Why is haptic perception essential in human robotic systems? This question is often posed in connection with humanoid robots. First of all, humanoid robots are intended to assist people in a typical human environment. A person expects a humanoid robot to think, move, act, and communicate in a human-like manner. This also includes the usage of typical human senses like vision, hearing and tactile sensing. Second, a robot manipulating items in an unstructured environment like a person's home needs to have some haptic feedback: information whether an item is firmly grasped or sliding is important for handling objects. Third, different kinds of haptic and tactile feedback are required for moving and acting in a human-built environment: collision detection just as well as haptic feedback for actions or control by a human operator.