Since the idea of the fuzzy set was proposed in 1965, many developments haveoccurred in this area. Applications have been made in such diverse areas as medicine,engineering, management, behavioral science, just to mention some. The application of thefuzzy sets involves different technologies, such as fuzzy clustering on image processing,classification, identification and fault detection, fuzzy controllers to map expert knowledgeinto control systems, fuzzy modeling combining expert knowledge, fuzzy optimization tosolve design problems. Fuzzy systems are used in the area of artificial intelligence as a wayto represent knowledge. This representation belongs to the paradigm of behavioralrepresentation in opposition to the structural representation (neural networks). Thefoundation of this paradigm is that intelligent behavior can be obtained by the use ofstructures that not necessarily resemble the human brain. A very interesting characteristic ofthe fuzzy systems is their capability to handle in the same framework numeric and linguisticinformation. This characteristic made these systems very useful to handle expert control tasks.