Ant colony optimization is a metaheuristic approach belonging to the model based search algorithm. It is a paradigm for designing metaheuristic algorithm for combinatorial problem. In this paper we discuss the Ant colony system. Ant colony system is one of the best algorithm of ant colony optimization. First we discuss the optimization,and one of the optimization problem is combinatiorial problem. To solve these types of problem Ant colony optimization was proposed. This paper contains description about Ant system and algorithm. Finally we discuss various applications of Ant colony optimization.

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Optimization combinatorial Optimization