a concept called ‘Approximate Reasoning’. It showed that vague logical statements enable the formation of algorithms that can use vague data to derive vague inferences. Zadeh assumed his approach would be beneficial above all in the study of complex humanistic systems. So the concept of a fuzzy logic system (FLS) as follows: ‘In general a FLS is a nonlinear mapping of an input data (feature) vector into a scalar output (the vector output case decomposes into a collection of independent multi-input/ single-output systems).