  The concept of intelligent system has emerged in information technology as a
type of system derived from successful applications of artificial intelligence.
The goal of this paper is to give a general description of an intelligent
system, which integrates previous approaches and takes into account recent
advances in artificial intelligence. The paper describes an intelligent system
in a generic way, identifying its main properties and functional components.
The presented description follows a pragmatic approach to be used in an
engineering context as a general framework to analyze and build intelligent
systems. Its generality and its use is illustrated with real-world system
examples and related with artificial intelligence methods.
