Recently, the fuzzy logic-based technique has received attention world-wide and has been becoming an emerging area with significant application possibilities. Fuzzy control theory is a combination of the fuzzy theory and the control system theory. It is a practical alternative for a variety of challenging control applications since it provides methods for designing non-linear controllers by the use of heuristic information. Fuzzy logic problems deal with situations that may have several reasonable solutions. The objective is to find the best of these possible solutions. Control systems based on the fuzzy logic theory can become more functional and flexible in comparison with conventional control systems. This book presents modern scientific knowledge in fuzzy logic control theory.