Piagets theory of cognitive development distinguishes 4 primary cognitive structures that correspond to 4 stages of development. He developed stages of theory of intellectual development that included these four distinct stages. The first stage of development, beginning at birth and continuing until age 2, is the sensorimotor stage. In this stage, children’s contact with the world around them depends entirely on the movements that they make and the sensations that they experience. These stages are in turn divided into distinct sub stages during which specific cognitive abilities emerge.The second stage is the preoperational stage. During this stage, which is marked by the acquisition of language, among other things, children become able to think in symbolic terms to form ideas from words and symbols. Children also begin to understand spatial and numerical concepts and the distinction between past and