Basic purpose of this article is to discuss on Cognitive Development Under Age of Six. Piaget called the cognitive development transpiring between ages 2 and 7 because preoperational stage. In this stage, children increase their using language and other symbols, imitation of adult conducts, and play. Young children develop a fascination with words—both “good” in addition to “bad. ” They in addition play “pretend” games. Piaget also described this stage with regard to what children cannot carry out.