The branch of computer science concerned with making computers
behave like humans. The term was coined in
1956 by John McCarthy at the Massachusetts Institute of Technology.
Artificial intelligence includes games playing: programming
computers to play games such as chess and checkers expert systems
: programming computers to make
decisions in real-life situations (for example, some expert systems
help doctors diagnose diseases based on
symptoms)  natural language : programming computers to understand
natural human languages neural networks : Systems that simulate
intelligence by attempting to reproduce the types of physical
connections that occur in animal brains
robotics : programming computers to see and hear and react to other
sensory stimuli. Currently, no computers exhibit full artificial
intelligence (that is, are able to simulate human behavior). The
greatest advances have occurred in the
field of games playing. The best computer chess programs are now
capable of beating humans. In May, 1997, an IBM super-computer
called Deep Blue defeated world chess champion Gary Kasparov in a
chess match.

In the area of robotics, computers are now widely used in assembly
plants, but they are capable only of very limited tasks. Robots have
great difficulty identifying objects based on appearance or feel, and
they still move and handle objects clumsily.

Natural-language processing offers the greatest potential rewards
because it would allow people to interact with computers without
needing any specialized knowledge. You could simply walk up to a
computer and talk to it. Unfortunately, programming computers to
understand natural languages has proved to be more difficult than
originally thought. Some rudimentary translation systems that
translate from one human language to another are in existence, but
they are not nearly as good as human translators. There are also voice
recognition systems that can convert spoken sounds into written
words, but they do not understand what they are writing; they simply
take dictation. Even these systems are quite limited -- you must
speak slowly and distinctly.

In the early 1980s, expert systems were believed to represent the
future of artificial intelligence and of computers in general. To date,
however, they have not lived up to expectations. Many expert systems
help human experts in such fields as medicine and engineering, but
they are very expensive to produce and are helpful only in special
situations.
Today, the hottest area of artificial intelligence is neural networks,
which are proving successful in a number of disciplines such as voice
recognition and natural-language processing.
There are several programming languages that are known as AI
languages because they are used almost exclusively for AI
applications. The two most common  are LISP and Prolog.
A computer application that performs a task that would otherwise be
performed by a human expert. For example,
there are expert systems that can diagnose human illnesses, make
financial forecasts, and schedule routes for delivery vehicles. Some
expert systems are designed to take the place of human experts, while
others are designed to aid them.
Expert systems are part of a general category of computer
applications known as artificial intelligence. To design an expert
system, one needs a knowledge engineer, an individual who studies
how human experts make decisions and translates the rules into terms
that a computer can understand.
 

A human language. For example, English, French, and Chinese are
natural languages. Computer languages,
such as FORTRAN and C, are not.  Probably the single most
challenging problem in computer science is to develop computers that
can understand natural languages. So far, the complete solution to
this problem has proved elusive, although a great deal of progress has
been made. Fourth-generation languages are the programming
languages closest to natural languages.
A type of artificial intelligence that attempts to imitate the way a
human brain works. Rather than using a digital model, in which all
computations manipulate zeros and ones, a neural network works by
creating connections between processing elements, the computer
equivalent of neurons. The organization and weights of the
connections determine the output.
Neural networks are particularly effective for predicting events when
the networks have a large database of prior examples to draw on.
Strictly speaking, a neural network implies a non-digital computer,
but neural networks can be simulated on digital computers.
The field of neural networks was pioneered by Bernard Widrow of
Stanford University in the 1950s. To date,
there are very few commercial applications of neural networks, but the
approach is beginning to prove useful in certain areas that involve
recognizing complex patterns, such as voice recognition.

The field of computer science and engineering concerned with
creating robots, devices that can move and react to sensory input.
Robotics is one branch of artificial intelligence. Robots are now widely
used in factories to perform
high-precision jobs such as welding and riveting. They are also used
in special situations that would be dangerous for humans -- for
example, in cleaning toxic wastes or defusing bombs.
Although great advances have been made in the field of robotics
during the last decade, robots are still not
very useful in everyday life, as they are too clumsy to perform
ordinary household chores.

Robot was coined by Czech playwright Karl Capek in his play R.U.R
(Rossum's Universal Robots), which opened
in Prague in 1921. Robota is the Czech word for forced labor. The term
robotics was introduced by writer Isaac
Asimov. In his science fiction book I, Robot, published in 1950, he
presented three laws of robotics:

1. A robot may not injure a human being, or, through inaction, allow a
human being to come to harm.

2. A robot must obey the orders given it by human beings except
where such orders would conflict with
the First Law.

3. A robot must protect its own existence as long as such protection
does not conflict with the First or
Second Law.