The four popular approaches to Artificial Intelligence are self-awareness, the theory of mind, limited memory, and reactive machines. Self-awareness is an exact replica of the AI shown in the movies. It requires technologies and extremely high-powered processing tools, which are not available today. The theory of mind caters to a machine that has the ability to assess its own goal and help in the development of other goals for other entities in the same environment that it operates in. The ability to react to the surroundings and learn from it is very important. Limited memory machines do not have a large amount of memory to store the immense amounts of data needed to constantly learn and develop. On the other hand, reactive machines are machines that have no memory or experience that they can use to learn from.
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