 As noted at the beginning of  section 10, robots are beginning to be equipped with web services, question answering abilities, chatbot techniques (for fall-back and entertainment), tutoring functions, and so on. The transfer of such technologies to robots has been slow, primarily because of the very difficult challenges involved in just equipping a robot with the hardware and software needed for basic visual perception, speech recognition, exploratory and goal-directed navigation (in the case of mobile robots), and object manipulation. However, the keen public interest in intelligent robots and their enormous economic potential (for household help, eldercare, medicine, education, entertainment, agriculture, industry, search and rescue, military missions, space exploration, and so on) will surely continue to energize the drive towards greater robotic intelligence and linguistic competence.