All terms
Foundations
Expert System
An early kind of AI that decides from hand-written rules instead of learning from data.
Definition
An expert system is an early style of AI that makes decisions by following a large set of hand-written 'if-then' rules, capturing a human expert's knowledge in a narrow field. Popular in the 1980s for tasks like medical diagnosis, expert systems were rigid and hard to maintain, and they were largely overtaken by machine learning.