This document provides an overview of genetic fuzzy systems. It begins with a recap of supervised and unsupervised machine learning techniques. It then discusses fuzzy logics and how they can be used to represent imprecise concepts using membership functions. Fuzzy systems that use fuzzy logic to model relationships between variables are introduced. Genetic fuzzy systems combine fuzzy systems with genetic algorithms to design the fuzzy rules, membership functions, and inference engines. The genetic algorithm evolves populations of candidate fuzzy systems through selection, crossover and mutation to optimize system performance.