The human brain is a remarkable system. Almost instantly, the brain allows us to perform a variety of complex tasks, such as recognizing people we know, performing sophisticated mathematical computations, and making critical decisions based on years of knowledge and training. While today's computers are now capable of crunching numbers significantly faster than the average human, they still lack the ability to perceive, reason, and learn as well as we do.
The field of Artificial Intelligence (AI) has been focused on closing the gap between humans and computers by attempting to equip machines with the ability to behave intelligently. Although the dream of an artificial human brain is far from being realized, we are now at a stage where a number of tasks that have traditionally been considered hard for computers to perform can now be accomplished fairly well. This allows us to create intelligent systems, which are devices and components that solve some practical problems that would traditionally require a human to perform. Examples of such intelligent systems in operation today include mobile devices that can translate and interpret foreign languages, software that can play chess like a grand master, and machines that can automatically analyze medical images such as CAT scans to discover tumors or bone fractures.