aims to create it. AI textbooks define the field as "the study and design of intelligent agents" where an intelligent
agent is a system that perceives its environment and takes actions that maximize its chances of success. John
McCarthy, who coined the term in 1955, defines it as "the science and engineering of making intelligent
machines."
AI research is highly technical and specialized, deeply divided into subfields that often fail to communicate with
each other. Some of the division is due to social and cultural factors: subfields have grown up around particular
institutions and the work of individual researchers. AI research is also divided by several technical issues. There are
subfields which are focused on the solution of specific problems, on one of several possible approaches, on the use
of widely differing tools and towards the accomplishment of particular applications. The central problems of AI
include such traits as reasoning, knowledge, planning, learning, communication, perception and the ability to move
and manipulate objects. General intelligence (or "strong AI") is still among the field's long term goals. Currently
popular approaches include statistical methods, computational intelligence and traditional symbolic AI. There are
an enormous number of tools used in AI, including versions of search and mathematical optimization, logic, methods
based on probability and economics, and many others.
The field was founded on the claim that a central property of humans, intelligence—the sapience of Homo sapiens—
can be so precisely described that it can be simulated by a machine. This raises philosophical issues about the nature
of the mind and the ethics of creating artificial beings, issues which have been addressed by myth, fiction and
philosophy since antiquity. Artificial intelligence has been the subject of optimism, but has also suffered setbacks
and, today, has become an essential part of the technology industry, providing the heavy lifting for many of the most
difficult problems in computer science.