Definition of Knowledge-Based Systems
Knowledge Based Systems derived from the term knowledge based expert system. This system is a system that uses human knowledge that has been stored in the computer to solve problems that require the expertise of an expert.
Knowledge Based Systems or System Expert is one of the branches of AI where the commercial world is called with a system that can effectively and efficiently carry out tasks that do not require too expert. Knowledge-Based Systems, also known as advisory system, knowledge systems, intelligent assistance systems work or operational systems.
Knowledge Based System Expert System is a program or giving advice / counsel computerized intended to mimic the process of reasoning (judgment) and the knowledge of experts in resolving problems more specific problems.
Expert System is a system that is trying to adopt human knowledge into a computer, so that the computer can complete as was done by experts.
Expert System was made in the area of ​​knowledge to something approaching a particular expertise in one field of human ability. Expert System try to find a satisfactory solution as did an expert. In addition Expert System can also provide an explanation of the measures taken and give the reasons for suggestion or conclusion found. This field is used more than the use of the fields other Artificial Intelligence. Expert System attracted huge interest in an organization due to its ability to increase productivity and to improve the working groups in the various specific fields where human expert would have difficulty in obtaining and maintaining that capability.

History of Knowledge Based Systems
Expert System developed by a community of First Instance AI (Artificial Intelligence) in mid 1956. Expert System that appears first is General-purpose Problem Solver (GPS) developed by Newel and Simon (Sri Kusumadewi, 2003). GPS and similar programs have a failure because its scope is too wide so sometimes it leaves important insights that should be provided.
Mid-1960s, a change of program rounder (general-purpose) into the specialist program (special-purpose) with the development of DENDRAL by E.Feigenbauh from Stanford University and then followed by MYCIN.
Beginning in the 1980s, Expert System technology is initially limited by the academic atmosphere began to emerge as commercial applications, particularly XCON, XSEL (developed on the R-1 at Digital Equipment Corp.) and CATS-1 (developed by General Electric). Expert System from year to year is always progressing.

There are several examples of expert systems ever created:
1. MYCIN
Provide diagnosis and treatment of disease.
2. Macsyma
Tackling the problem of mathematics.
3. DENDRAL
Identifying the molecular structure of an unknown mixture.
4. XCON & XSEL
Help large computer system configuration.
5. SOPHIE
Conduct analysis of electronic circuits.
6. Prospector
Help locate and find the deposit geology.
7. FOLIO
Help give a decision for a manager in terms of stock brokers and investment.
8. DELTA
Maintenance of diesel locomotives.